Borderline personality disorder (BPD) has attracted considerable research interest for several decades, both to understand its origins and to refine its clinical management. In practice it occupies an important place in psychiatry and psychotherapy: epidemiological studies indicate that it may account for up to 10% of patients seen in outpatient psychiatric consultations and up to 20% of patients hospitalised in psychiatry.

Its impact in therapy is therefore major. The people concerned often present suicidal behaviours, self-harm, intense mood swings and chaotic interpersonal relationships, which put the therapist’s skills to the test. Working with these patients can prove demanding: managing crisis, acting out, radical shifts of relational position (idealisation followed by rejection), or splitting, which often sets professionals against one another.

Nevertheless, with a fine-grained understanding of the disorder and a suitable approach, clinicians can help these patients regain stability and significantly improve their quality of life. That is the purpose of this educational synthesis, which combines academic references with plain-language explanation.

Definition and diagnostic criteria (DSM-5-TR)

BPD belongs to the group of personality disorders and its diagnosis rests on well-established criteria. According to the DSM-5-TR (2022), it is a general pattern of instability in interpersonal relationships, self-image and affects, with impulsivity, beginning in adolescence or early adulthood. The diagnosis requires the presence of at least five of the following nine criteria.

It is important to note that these symptoms must cause significant distress or impairment of functioning for the diagnosis to be made.

Clinically, BPD is delicate to diagnose in young people. The DSM-5-TR indeed recommends not diagnosing a personality disorder before the age of 18. In practice, however, some clinicians make the diagnosis in adolescents when symptoms are clear and persistent. A growing body of data suggests that BPD can manifest in adolescence, albeit with less stability than in adults. Cailhol and colleagues (2015) stress that, despite the controversies, using the concept of borderline personality in adolescence is justified by various converging arguments, notably the continuity of certain symptoms between adolescence and adulthood.

Luigi Cancrini and the metaphor of the borderline ocean

Psychiatrist and psychotherapist Luigi Cancrini offers an original reading of the disorder through the metaphor of the borderline ocean, the title of his 2009 book. In his view, borderline states form a vast psychic ocean. The metaphor illustrates how many disorders or behaviours, once scattered between neurotic and psychotic categories, in fact belong to a borderline level that is intermediate and protean.

Cancrini develops the idea that borderline functioning corresponds less to a fixed, timeless personality structure than to a contextual and episodic mode of psychic functioning. The term thus covers states of regression and psychic suffering that may vary over a lifetime and according to circumstances. This ocean is populated by a wide range of clinical cases, from wounded children — victims of maltreatment or emotional deprivation, in whom borderline protective mechanisms can be observed — to adults who succumb to these limit states during episodes of existential crisis.

Cancrini illustrates his argument with genuine clinical travelogues, in the manner of an explorer navigating this psychic ocean. His integrative approach draws both on psychoanalysis — notably theories of dissociation and of the splitting of the ego in the face of trauma — and on systemic and contextual approaches.

This view is particularly useful for the care of patients who often come from traumatic or dysfunctional family environments. In short, the oceanic metaphor reminds therapists that these patients navigate a vast emotional universe whose diversity and fluidity must be acknowledged, rather than confined to a rigid diagnostic box.

A systemic reading of family and relational issues

The systemic approach sheds fundamental light on borderline functioning by considering the patient within their family and relational context. The symptoms — instability, impulsivity, suicidal threats — have strong interpersonal resonances. They can be understood as the expression of an imbalance within the person’s family or social system.

In many cases, the person occupies the function of “identified patient” within their family, their extreme behaviour bringing to light the system’s relational dysfunctions or transgenerational traumas. Histories of maltreatment, neglect or conflictual parental separation are frequently found, suggesting a ground of insecure attachment and an unpredictable environment. The systemic reading seeks to decode how those around the patient may unintentionally maintain or reinforce the difficulties — through overprotective attitudes, paradoxical communication, or on the contrary rejection and stigmatisation — and how, in return, the patient’s behaviour influences the family system, for instance by polarising relationships around permanent crisis.

Working the family bond is thus an integral part of treatment. Yet, as Pigeon and Mazzetti (2017) note, “caring for […] a borderline patient proves difficult in many respects […] but even more than the symptomatology […] it seems to us that working with their families is particularly problematic”. These families may be exhausted, at a loss, or in deep conflict with the patient, making therapeutic collaboration arduous. Despite these difficulties, involving the family can be decisive in improving the outcome of therapy.

A systemic reading of interactions makes it possible in particular to identify phenomena of isomorphism between the family and care institutions, that is, parallels between family relationships and those that develop with the care team. A patient who divides their family into “good” and “bad” may reproduce this pattern with caregivers, some being idealised and others devalued. If the team becomes aware of it, it can adopt a coherent position and avoid these relational traps. Likewise, understanding the patient’s role in the family dynamic — scapegoat of a parental couple in crisis, or on the contrary regulating element of a chaotic family — helps the therapist adjust their intervention.

The different therapeutic approaches

Faced with the complexity of the disorder, there is no single solution: a range of approaches can be mobilised, ideally in a coordinated and personalised way. Four major dimensions stand out.

Individual and family systemic therapy

The systemic approach aims to modify the dysfunctional interactions and negative feedback loops that maintain the disorder. In family therapy, the therapist meets the patient together with family members — parents, partner, siblings — to help them communicate better, step out of cycles of emotional escalation or withdrawal, and find calmer ways of functioning. The work may consist, for instance, in helping parents respond to crises with empathic listening and a containing framework, rather than with anxiety or anger alone.

An integrative, multi-systemic approach is particularly useful in acute crisis situations, notably with suicidal adolescents. Har and Roche-Rabreau (2010) recommend closely articulating individual crisis intervention with family and institutional work: family crisis interviews as soon as the patient is admitted, in order to untangle urgent misunderstandings; coordination with the ward’s caregivers to ensure consistency in the messages given to the young person; and family follow-up after discharge to consolidate progress.

Individual therapy, even when it is not explicitly systemic, also gains from integrating the relational dimension. Modern psychodynamic approaches, such as Otto Kernberg’s transference-focused psychotherapy (TFP), were designed specifically for BPD: they aim to help patients integrate their contradictory representations of themselves and of others, using the therapeutic relationship as a microcosm of their usual relationships. Taking the patient’s relational system into account — family or dyadic — is therefore a central lever of treatment.

Multi-family groups

Extending the systemic approach, multi-family groups bring together several patients and their families within a single therapeutic group. Originally created for the treatment of severe disorders such as schizophrenia, they are also relevant in BPD, where those around the patient play a key role. The principle is to gather four to six families affected by similar difficulties and to co-facilitate collective sessions focused on sharing experience, mutual support and problem-solving.

Brice Martin and colleagues (2014) stress that including families has become an “inescapable necessity” in psychosocial rehabilitation, both to relieve the psychic suffering of relatives and to draw on them as partners in care. Families, often in great distress, find in this setting a space to share their experience with other parents “who understand”, which breaks their isolation and reduces their sense of guilt or powerlessness. From the patient’s side, seeing others grappling with comparable difficulties helps to shift perspective and to learn coping strategies from peers.

The therapist, for their part, uses systemic principles to run the group: encouraging constructive interactions between families, highlighting shared relational patterns, and inviting participants to experiment with new ways of interacting. In one session, a mother may explain how she now manages to defuse her daughter’s outbursts by keeping a calm tone and setting a clear framework; the other parents take this as a model and can try it at home. A clinical vignette presented by Martin and colleagues illustrates the value of the setting: a young patient, until then unresponsive to therapy, was able to make progress thanks to his parents’ participation in a multi-family group, where they became aware of the impact of their own communication on their son’s reactions — which led to notable changes at home, with fewer daily arguments and the restoration of a constructive dialogue.

Multi-family groups are of course no panacea: some relatives are reluctant to expose themselves in a group, and the setting requires facilitators trained both in family therapy and in group techniques. More and more psychiatric teams nevertheless include it, with generally positive feedback on the therapeutic alliance and on the reduction of relapses.

Dialectical behaviour therapy (DBT)

Developed by Marsha Linehan in the 1990s, DBT is today one of the reference treatments for borderline personality disorder. It rests on a cognitive-behavioural model integrated with dialectical and mindfulness principles. The central dialectic consists in working on acceptance of oneself and of one’s emotions on the one hand, while encouraging change in problematic behaviours on the other.

In practice, DBT combines weekly individual therapy focused on emotion regulation and the management of suicidal crises, group skills training (mindfulness, distress tolerance, emotion regulation and interpersonal effectiveness modules), telephone coaching in case of crisis between sessions, and a consultation team for the therapists in order to maintain consistency of treatment.

Many studies have demonstrated its effectiveness in reducing suicidal behaviours, self-harm and hospitalisations in chronic borderline patients. Linehan and colleagues (1991) showed that a one-year DBT programme significantly reduced suicide attempts and improved patients’ engagement in care, compared with conventional psychotherapy.

Psychoeducation and support for families

A final essential component concerns psychoeducational work and support for those around the patient. Psychoeducation consists in explaining to the patient and their relatives, in accessible language, the nature of the disorder, its symptoms, its course and the available treatments. For the patient, understanding their own functioning better — realising, for instance, that their fears of abandonment are part of the disorder and do not mean they are “mad” — brings relief and reduces shame or guilt.

For the family, acquiring knowledge about BPD makes it possible to depersonalise certain behaviours: relatives come to understand that their child’s or partner’s outbursts and fluctuations are not intentionally directed against them, but stem from uncontrollable inner suffering. This understanding fosters empathy and prevents inappropriate reactions.

Psychoeducation also includes learning communication and crisis-management strategies. Specific programmes, such as Family Connections, developed by the NEA-BPD association, teach relatives techniques borrowed from DBT to respond better to risky behaviours, to set caring limits and to encourage the patient in their efforts. Including families in the care plan as early as possible is recommended: this may take the form of support groups facilitated by professionals, or joint family consultations with the patient.

Martin and colleagues (2014) note that the family can become “a precious partner in care and an important lever for change” if it is supported and appropriately included in the therapeutic process. Not all families can or wish to be involved in the same way, and each person’s pace must be respected; but even minimal support — a few informational meetings, the provision of educational documents — can improve the therapeutic alliance and the patient’s environment. Finally, the exhaustion experienced by many relatives should not be forgotten. Offering families a space to speak, acknowledging their distress and, where appropriate, directing them towards psychological support for themselves, is an integral part of a comprehensive approach.

Two clinical illustrations

To make these approaches more concrete, here are two clinical situations — fictional, but inspired by real cases — and the way a plural therapeutic strategy was able to help.

Julie, 17

Julie was admitted to hospital after a suicide attempt by medication overdose. Since the age of 15 she has presented major emotional instability, with self-harm, unpredictable outbursts of anger and turbulent relationships with those around her. Her parents are at a loss: they describe their daughter as “unmanageable, going from laughter to tears in an instant” and admit to living in constant fear that a tragedy will occur. In an adolescent unit, a diagnosis of emerging borderline personality disorder is made.

The team sets up a crisis plan to keep Julie safe — a no-suicide contract, removal of dangerous objects — then gradually introduces dialectical behaviour therapy. Alongside individual sessions in which she identifies her emotions and learns stress-management exercises, psychoeducation workshops teach her mindfulness and emotion-regulation skills in a group. Julie learns, for example, to recognise the onset of her anger — tachycardia, persecutory thoughts — and to apply the so-called “dive” technique, which consists in splashing cold water on one’s face to bring down emotional intensity, rather than cutting herself.

Her parents, for their part, are invited to take part in a few family sessions. There, the systemic therapist facilitates a dialogue in which each can express how they feel: the mother puts words to her fear of losing her daughter and to her tendency to monitor Julie’s every move, which stifles her; the father admits that he clumsily minimises his daughter’s distress, thinking he is doing the right thing by telling her to “pull herself together”. The family manages to reach new agreements: the parents commit to adapting their communication, avoiding frontal criticism and valuing Julie’s efforts, while Julie agrees to share her emotions before they overflow and to warn her parents when she feels in danger.

After six months the course is positive: Julie has made no further suicide attempt, her self-injuries have decreased in frequency, and tension at home has clearly eased. Not everything is resolved — she remains vulnerable to romantic disappointments and to conflicts with her friends — but she and her family now have tools to weather these storms without capsizing.

Karim, 23

Karim’s path has been marked by violence and rupture. An only child, he grew up with an authoritarian father and a depressed mother. In adolescence he dropped out of school, used drugs and committed a series of petty offences. Diagnosed as “borderline” at 18 after several psychiatric admissions for self-aggressive acts and fights, he also spent time in detention. On leaving prison, the family climate is explosive: according to the care team, “the parents, feeling overwhelmed, reject this uncontrollable son”. After yet another argument with his father, Karim attempts to hang himself, which leads to a long hospital stay, close to two years, in a psychiatric ward.

The team decides to work in depth with the family by adopting a multi-systemic approach involving parents, patient and caregivers. Several family interviews are first held in hospital, with a systemic therapist who helps each person voice their grievances within a safe framework. The parents alternately confess their anger, their shame in front of those around them — “what did we do for him to turn out this way?” — and their despair about their son’s future. Karim, for his part, expresses for the first time his resentment towards a father he perceives as tyrannical, and his guilt at hurting his mother through his actions. This dialogue, though painful, opens a breach towards mutual understanding.

In parallel, Karim receives individual psychotherapy inspired by TFP, in which he explores how his internalised parental images influence his current behaviour: he realises, for instance, that he provokes figures of authority — caregivers, educators — as he did with his father, out of an unconscious fear of being subjugated. Over the months, a multi-family group is offered, bringing together his parents and other families facing similar difficulties with their adult child. The experience proves highly constructive: these parents, who believed themselves alone in the chaos, find support among other couples living through comparable situations, and exchange views on how to react — or not react — to crises. Having rejected their son, they begin to separate the disorder from the person: they come to understand that Karim is not merely “uncontrollable”, that he suffers and does not know how to handle his anxiety other than through violence or excess. Gradually, a solid therapeutic alliance forms between the family and the team.

Towards the end of the hospital stay, an extended meeting is organised with external partners — social worker, addiction service, employment support worker — to prepare Karim’s discharge. A plan is built: accommodation in a therapeutic flat, intensive outpatient follow-up with DBT in a day hospital, and continued monthly family sessions. One year after discharge, Karim has returned neither to hospital nor to prison. He is in vocational training. Relations with his parents have become cordial again: a framework of regular contact has been established, and each respects the other’s limits. This case shows that with patience, multi-family and institutional coordination, and family involvement despite the initial wounds, even the most complex situations can evolve favourably.

Prospects and a message of hope

Despite its reputation as a “difficult” disorder, often portrayed pessimistically, borderline personality disorder today has encouraging prospects. On the one hand, therapeutic advances offer real hope of recovery: combined approaches — specialised individual therapies, family work, groups, psychosocial interventions — achieve significant improvement in the majority of patients. On the other hand, the natural course of the disorder is often more favourable than was once thought. Longitudinal follow-ups have shown that the great majority of patients see their symptoms subside over time.

In other words, remission is possible in most cases, especially when the patient benefits from suitable support. “Remission” obviously does not mean the complete disappearance of every difficulty: it means a reduction of symptoms below the diagnostic threshold, and a borderline past can leave scars, in terms of self-esteem or of lost relationships. This finding nevertheless counters the idea of inevitable chronicity.

For therapists, the message is twofold. We must keep in mind the extreme suffering and the experience of abandonment that underlie borderline behaviour: this calls for an empathic, patient stance, and for avoiding the trap of the rejection or over-involvement the patient may provoke in us. It is equally essential to believe in these patients’ potential for positive change. With coherent interventions, multidisciplinary teamwork including the patient and their relatives, and a good alliance, deep changes can be observed: people who manage to maintain stable relationships, to identify and put words to their emotions without harming themselves, to build life plans. Every small step forward — a week without self-harm, a session in which the patient expresses their pain instead of discharging it aggressively, a parent who responds calmly to a provocation — paves the way to resilience.

Borderline personality therefore requires of the therapist a fine-grained understanding, like that of a navigator on a sometimes raging ocean, and a diversified toolbox to adapt to the patient’s changing needs. The educational, integrative and human approach — such as the one advocated by Cancrini and by multi-systemic approaches — shows that it is possible to help these patients find a new balance. The road is often long and winding, but far from being a dead end. The challenge for the therapeutic community is to keep refining these approaches, to include families and networks in them, and to cultivate that hope: in the end, it is hope that guides the way to change.

Sources

• Cancrini, L. (2009). L’océan borderline: troubles des états limites, récits de voyage. Brussels: De Boeck.
• Cailhol, L., Gicquel, L., & Raynaud, J.-P. (2015). Trouble de la personnalité borderline à l’adolescence. In IACAPAP e-Textbook of Child and Adolescent Mental Health (French edition, ch. H.4).
• Har, A., & Roche-Rabreau, D. (2010). Vers une approche intégrative et multi-systémique de l’adolescent suicidant et de sa famille. Thérapie Familiale, 31(2), 133-149.
• Martin, B., Rochet, C., Félus, D., Félus, M., & Franck, N. (2014). Réhabilitation et groupes multifamiliaux à orientation systémique. L’Information psychiatrique, 90(6), 477-484.
• Pigeon, H., & Mazzetti, C. (2017). Quel travail possible avec la famille d’un patient diagnostiqué état limite ? Lecture systémique des enjeux familiaux et institutionnels autour d’un patient état limite hospitalisé. L’Information psychiatrique, 93(10), 859-864.

All of these markers are taken up and commented on in the video below, in French.