What is borderline personality disorder splitting?

Dr. Jenni Jacobsen, PhD
Author: Dr. Jenni Jacobsen, PhD Medical Reviewer: Dr. Brittany Ferri, PhD Last updated:

Borderline personality disorder is a mental health condition associated with a lack of emotion control and a tendency to see the world as all good or all bad [1]. Because people with borderline personality disorder often see the world in black and white, they are likely to show a symptom called splitting, which is described in more detail below.

What is borderline personality disorder splitting?

What is splitting in borderline personality disorder?

Individuals who live with borderline personality disorder (BPD) tend to view people and situations in extremes; a person is either all good, or at the opposite end of the spectrum, they are horrible [1]. In the context of relationships, BPD splitting means that people are viewed in extremes.

Mental health researchers have described BPD splitting as shifts in the way that objects and people are perceived. More specifically, splitting is a cognitive and emotional disturbance in which people with BPD fluctuate between idealizing a person or object one moment, and then devaluing this person or object the next moment [2].

What causes BPD splitting?

BPD splitting can be a common presentation in borderline personality disorder, because of the fact that this mental health condition comes with extreme mood swings as well as a tendency to view situations and people in extremes [1]

Researchers have taken an interest in learning the causes of BPD splitting, and they have arrived at some informative conclusions. For example, one recent study suggests that BPD splitting is the result of emotional reactivity and irritability [2].

When a person with borderline personality disorder experiences shifts in their emotional perception of people or objects, they experience tension. This tension is actually the result of brain activity in specific regions responsible for emotional regulation and the processing of threats. The outcome of this tension is viewing people as either all good or all bad [2].

Other psychology experts have reported that the tendency for people with BPD to have a paranoid view of personal relationships explains splitting. Individuals who have BPD believe that everyone will eventually betray or abandon them, so while they may have brief periods of idealizing significant others or close friends, as soon as they feel betrayed, they “split” and view the person in a persecutory fashion [3]

One theory underlying splitting in BPD is the object relations theory. This theory states that our early life experiences shape the way we see the world. People with a healthy sense of self are able to integrate positive and negative aspects of themselves and others into one whole. They accept themselves and other people, flaws and all [4].

People who experience BPD splitting have not developed this healthy integration of positive and negative. Instead of viewing people and situations as being a mix of positive and negative characteristics, they “split” people into extremes of good and bad. Splitting represents a defense mechanism that allows a person with BPD to protect idealized, “perfect” ways of thinking from negative thoughts and emotions at the other end of the spectrum [4].

Ultimately, splitting reduces anxiety for people with BPD, but it is a dysfunctional reaction to the environment. Splitting the world into dichotomies results in chaotic, unstable relationships with others, as well as intense mood swings [4].

Signs of BPD splitting

Someone who displays BPD splitting behaviors is likely to show some or many of the following signs:

  • Rapid mood swings, shifting from happy and content to enraged with little warning
  • Viewing others’ behavior as being intentionally hurtful, even in the case of innocent mistakes
  • Abruptly ending relationships, including friendships and romantic partnerships, because of one perceived slight or disagreement
  • Believing that a person or object is suddenly egregiously bad because of one negative experience (ie: believing that one disagreement with a boss means that the boss is incompetent)
  • Viewing a friend or significant other as perfect one minute and then awful the next

Effects of splitting

While BPD splitting is used as a defense mechanism against stress or negative feelings, the reality is that it typically leads to worse functioning for individuals who live with BPD.

Ultimately, BPD splitting is linked to the following consequences:

  • Unstable relationships: The act of viewing a partner as perfect one minute and then awful the next leads to chaotic, unstable relationships [4]. The rapid shift from idealizing to devaluing a partner is typically associated with conflict. Being unable to accept a partner for their strengths and weaknesses means that every relationship will ultimately cause distress for a person with BPD, because they will view their partner as being awful as soon as they see signs of flaws or mistakes.

This way of thinking leads a person with BPD to push their partner away as a defense mechanism, later pulling them back in when they shift back to seeing their partner positively. The significant other is likely to end the relationship when the stress of splitting becomes too much for them to manage.

  • Difficulty with functioning in important areas of life:The tendency to engage in splitting can make it difficult to function effectively in major areas of life, such as in the workplace. When a person with BPD feels slighted or treated unfairly, they may view a once respected boss as being worthy of contempt, leading to inappropriate behavior, such as verbal aggression. This can lead to workplace discipline, or even the loss of a job.
  • Depressed moods: BPD splitting may be an attempt to defend the self against anxiety, tension, or negative self-perceptions, but this behavior ultimately leads to a depressed mood. Because of the tendency to split, a person with BPD can quickly shift to a negative emotional state with one bad event [4]. For example, a minor frustration may convince the person that the entire day is ruined.
  • Distorted thinking: The tendency to view the world in extremes of good and bad also leads to distorted, rigid thinking patterns. With splitting, thinking becomes rigid, and all external events are viewed in a distorted way. The person who engages in BPD splitting cannot cope with ambiguity or unexpected events, which makes it difficult to adjust to the demands of life. In fact, it is the distorted thinking surrounding splitting that actually leads to many BPD symptoms, such as mood swings, chaotic relationships, unstable self-image, impulsive behaviors, and attempts to avoid abandonment [4].

How long do episodes last?

The length of a BPD splitting episode can vary widely, depending upon the severity of a person’s symptoms, the nature of the event that led to splitting, and the person’s unique situation and personality. Episodes can last from a few hours, up to a few days [1].

For instance, a person who lives with BPD may be triggered by a conflict with a significant other, and view that person very negatively for a few hours. After their mood shifts to positive again, they may abruptly revert to idealizing their significant other. In cases of extreme conflict or distress, a person with BPD may devalue their partner for days at a time. This behavior can understandably be confusing for the partner and damaging for the relationship.

Managing BPD splitting episodes

If your loved one lives with BPD, knowing how to manage splitting episodes can be challenging, because these episodes can be upsetting and confusing for you. The following tips can make it easier for you to manage:

  • Learn about symptoms of BPD: Learning about the nature of BPD will help you to understand what your loved one is experiencing.
  • Remember not to take the behavior personally: You’ll be better able to cope with your loved one’s symptoms if you recognize that they are the result of a mental health disorder, and not a reflection on you as a person.
  • Practice empathy: You may be tempted to lose your temper or argue with your loved one when they are splitting, but this will only make matters worse. Instead, practice empathy by expressing that you understand they are frustrated and struggling with distress.
  • Remind the person that you love them: When a person is in the midst of a splitting episode, they are likely to be argumentative and perhaps verbally aggressive, which makes it difficult for them to see you in a positive light. Remind the person that you love them, which may diffuse some of the conflict.
  • Encourage your loved one to seek treatment: Borderline personality disorder is a legitimate mental health condition, and because of the severity of the symptoms, people often need treatment. Support your loved one in reaching out for help.
  • Set boundaries: BPD is a mental health condition, but that doesn’t mean you have to tolerate abusive or dangerous behavior from someone with BPD. It’s important for you to set clear boundaries and communicate what behavior you will not tolerate. You may need to step away from the relationship to care for your own needs.

Treatment for BPD

Although there is no cure for BPD, there are effective treatments that can reduce the severity of symptoms, including BPD splitting. Therapy is the most well-researched modality for treating BPD, but some medications may be effective in combination with therapy.

Some common therapeutic modalities for BPD include [5]

  • Dialectical Behavior Therapy (DBT): This therapeutic method teaches skills for managing distress, regulating emotions, and navigating relationships. It focuses on becoming more mindful and includes individual and group therapy sessions.
  • Mentalization-Based Treatment (MBT): This form of therapy helps individuals with BPD to develop the skill of mentalization, which involves taking a look at one’s own thoughts and feelings, as well as imagining the thoughts and feelings in others’ minds. The goal is for patients with BPD to develop the ability to mentalize when under stress, which allows them to be more flexible when making sense of interpersonal situations.
  • Schema-Focused Therapy (SFT): SFT focuses on helping patients with BPD to change their negative patterns of thinking, feeling, and behaving and replacing them with more functional patterns. This approach believes that people with BPD have distorted schemas that control their life, but with a strong relationship with a therapist, they can begin to correct these schemas.
  • Transference-Focused Psychotherapy (TFP): With roots in psychoanalytic theory, this model seeks to correct primitive defense mechanisms by taking a look at how a patient interacts with their therapist. These patient-therapist interactions uncover the dysfunctional patterns that a person uses in interpersonal relationships, so that they can be corrected.

Beyond specific therapeutic modalities, people with BPD can benefit from participating in case management services, support groups, and psychoeducational groups to help them learn about their mental health condition and access additional supports within the community. 

While not recommended as a standalone treatment for BPD, medications may be used to treat specific symptoms, such as difficulties with emotional regulation and impulsive behavior. Mood stabilizers and antipsychotic medications can be effective for reducing symptom severity, according to available research. Ultimately, medications will be prescribed on a case-by-case basis, with the goal of maximizing benefit while minimizing harm. In many cases, medication is an add-on to other BPD treatment plans, such as counseling and support groups [5].

  1. National Institute of Mental Health. (2022, April). Borderline personality disorder. Retrieved November 17, 2022, from https://www.nimh.nih.gov/health/topics/borderline-personality-disorder
  2. Pec, O., Bob, P., & Raboch, J. (2014). Splitting in schizophrenia and borderline personality disorder. PLOS ONE, 9(3), e91228. https://doi.org/10.1371/journal.pone.0091228
  3. Fertuck, E.A., Fischer, S., & Beeney, J. (2018). Social cognition and borderline personality disorder: Splitting and trust impairment findings. The Psychiatric Clinics of North America, 41(4), 613-632. doi: 10.1016/j.psc.2018.07.003.
  4. Clarkin, J.F., Lenzenweger, M.F., Yeomans, F., Levy, K.N., & Kernberg, O.F. (2007). An object relations model of borderline pathology. Journal of Personality Disorders, 21(5), 474-499. Retrieved from https://tarjomefa.com/wp-content/uploads/2019/05/9488-English-TarjomeFa.pdf
  5. Choi-Kain, L.W., Finch, E.F., Masland, S.R., Jenkins, J.A., & Unruh, B.T. (2017). What works in the treatment of borderline personality disorder. Current Behavioral Neuroscience Reports, 4, 21-30. https://doi.org/10.1007/s40473-017-0103-z
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Dr. Jenni Jacobsen, PhD
Author Dr. Jenni Jacobsen, PhD Medical Reviewer, Writer

Dr. Jenni Jacobsen, PhD is a medical reviewer, licensed social worker, and behavioral health consultant, holding a PhD in clinical psychology.

Published: Jan 12th 2023, Last edited: Sep 26th 2023

Brittany Ferri
Medical Reviewer Dr. Brittany Ferri, PhD OTR/L

Dr. Brittany Ferri, PhD, is a medical reviewer and subject matter expert in behavioral health, pediatrics, and telehealth.

Content reviewed by a medical professional. Last reviewed: Jan 12th 2023