Splitting and Borderline Personality Disorder

A defense mechanism where everything is black or white

Trying to make him understand
PeopleImages/Getty Images

Splitting is a term used in psychiatry to describe the inability to hold opposing thoughts, feelings, or beliefs. Some might say that a person who splits see the world in terms of black or white. It is a distorted way of thinking in which the positive or negative attributes of a person or event are neither weighed nor cohesive.

Splitting is considered a defense mechanism by which people with borderline personality disorder (BPD) can view people, events, or even themselves in all or nothing terms.

Splitting allows them to readily discard things they have assigned as "bad" and to embrace things they consider "good," even if they are harmful or risky. Splitting is one of the nine criteria used to diagnosed BPD.


Splitting can interfere with relationships and lead to intense and self-destructive behaviors. A person who splits will typically frame people or events in terms that are absolute with no middle ground for discussion. Examples include:

  • Things are either "always" or "never."
  • People can either be "evil" and "crooked" or "angels" and "perfect."
  • Opportunities can either have "no risk" or be a "complete con."
  • Science, history, or news is either a "complete fact" or a "complete lie."
  • When things go wrong, a person will feel "cheated," "ruined," or "screwed."

What makes splitting all the more confusing is that the belief can sometimes be iron-clad or shift back-and-forth from one moment to the next.

People who split are often seen to be overly dramatic or overwrought, especially when declaring that things have either "completely fallen apart" or "completely turned around." Such behavior can be exhausting to those around them.

Accompanying Features 

In isolation, splitting may seem almost commonplace, a behavior easily attributed to any number of individuals we know.

However, with BPD, it is considered a consistent and distorted behavior usually accompanied by other symptoms, such as:

  • Acting out (performing an action without consideration to consequence)
  • Passive aggression (an indirect expression of hostility)
  • Denial (the conscious action of ignoring a fact or reality)
  • Projection (assigning an undesirable emotion to someone else)
  • Omnipotence (the belief that one possesses superiority in intelligence or power)
  • Emotional hypochondriasis (emotional hypochondria)
  • Projective identification (becoming fixated with undesirable emotions that someone had projected onto you)

How BPD Is Diagnosed

A BPD diagnosis can only be made by a qualified mental health specialist. To make the diagnosis, the doctor would need to confirm five of nine symptoms outlined in the Diagnostic and Statistical Manual of Mental Disorders (DSM-5):

  • Intense and stormy relationships that involve splitting
  • Feeling persistently empty or bored
  • A warped view of oneself that affects emotions, values, moods, and relationships
  • Impulsive behavior, such as abusing substances or driving recklessly
  • Anger issues, such as violent outbursts followed by extreme guilt and remorse
  • Extreme attempts to avoid abandonment or extreme feelings of abandonment

Caring for a Loved One With BPD

There is no easy answer on how to deal with a loved one who has extreme symptoms of BPD. How you cope depends largely on the nature of your relationship and the impact it is having on your family. With that being said, there are some guiding principles that may help:

  • Cultivate empathy. Start by reminding yourself that splitting is part of the disorder. While certain actions may seem intentional and manipulative, your loved one is not doing this to gain satisfaction. They are simply defense mechanisms the person turns to whenever he or she feels defenseless.
  • Try to manage your response. If your loved one has BPD, try to remember that you are in the better position control your temper. Yelling or engaging in hostility will only serve to make the situation even worse.
  • Remind your loved one that you care. People with BPD are often terrified of being rejected or abandoned. Knowing that someone cares often helps reduce the splitting behavior.
  • Maintain lines of communication. Discussing a situation when it happens allows you to isolate that event rather than piling one atop the next. Failure to communicate only serves to fuel your loved one's rejection anxiety.
  • Set boundaries. Dealing with the challenges of BPD is one thing; becoming the object of abuse is another. Always set limits with a loved one who has BPD. If that line is ever crossed, explain why you are backing away and try to do so dispassionately. Setting boundaries help preserve the relationship rather than challenging it.
  • Take care of yourself. This may include finding your own therapist to help you balance your needs along with those of your loved one.

There may be times where you will need to take more drastic action. In the event that the relationship is harming your family, your work, and your sense of well-being, you may be faced with the reality that the relationship cannot continue.

While this is an incredibly painful choice for everyone involved, it can also be the most healthy in some cases. If needed, the decision should be made with the help of a qualified mental health professional.


American Psychiatric Association (APA). Diagnostic and Statistical Manual of Mental Disorders (DSM-5). Arlington, Virginia; 2013.

APA. "Practice Guideline for the Treatment of Patients with Borderline Personality Disorder." American Journal of Psychiatry. 2010; 158:1-52.

Scheirs, J. and Bok, S. "Psychological distress in caretakers or relatives of patients with borderline personality disorder." ​International Journal of Social Psychiatry. 2007; 53(3):195-203.

Continue Reading