Picture this scenario: Your relationship history with Maria is drenched in drama. Two years ago, when she started working alongside you in your office area, she was nothing short of a delight. She was kind, generous, funny, and always a joy for you to be around. You quickly became friends and you truly valued this friendship.
On occasion, she would badmouth some of your colleagues. You were surprised that she often did so in a flagrant, if not downright nasty manner. This set of actions seemed incongruous with your take on her as a generally kind soul.
One day at the coffee machine, Maria caught you off guard: Did you really just use up all the water and not fill it up? Are you f’n serious?! … She belted, with a tone more serious than you possibly expected.
You smiled at her, thinking that she must be joking. Her eyes, looking directly back into your own, suggested otherwise. She was nothing short of furious in the moment.
From that moment on, Maria seems to have an all-out vendetta against you. She refuses to acknowledge your presence in daily interactions. She complains about actions that you never even engaged in to your supervisor and to other colleagues. To be frank, she now scares you. You decide to distance yourself from her as much as possible. You even consider applying to other jobs.
You want nothing to do with Maria again, ever.
Borderline Personality and Social Relationships
Across development, human personality is highly malleable and can go in a variety of directions. One of the major disorders of personality, attributed to problems during development, is borderline personality, characterized by a tendency to quickly and often unpredictably oscillate between love and hate for others, subpar emotional regulation, and consistent problems in interpersonal relationships (see Carlson et al., 2009).
Stepping back a bit, it seems that Maria, from the example above, fits a classic borderline personality type. She oscillates between love and hate very quickly. She is socially unpredictable. And her inability to temper her own emotions seems to get in the way of even her closest relationships.
People with borderline personality tendencies tend to have major social problems. And they tend to cause problems in social contexts that are otherwise quite harmonious.
The Evolutionary Psychology of Estrangements and Borderline Personality
In a recent study of the psychology of estrangements, Annie Sung and collaborators (2021) set to explore psychological predictors of how many estrangements one has in life. Past research on this topic (see Geher et al., 2019) found that the number of people from whom one is fully estranged is associated with such outcomes as having poor social support, anxious attachments to others, depressive tendencies, and a dark approach to dealing with others. In short, the number of estrangements one has in life seems to be a ubiquitous predictor of poor psychological and social functioning across the board.
From an evolutionary perspective, it makes full sense that people with many estrangements have a variety of other problems in life. After all, for the lion’s share of human evolutionary history, we lived in small, tight-knit groups that numbered no more than 150 (See Dunbar, 1992). Others in your nomadic clan were people you were going to have to deal with and depend on for your entire life. And having severely negative relationships with even a small number of them—severe enough to lead to lifelong estrangements—would surely have had long-term adverse consequences that could have threatened one’s survival and/or reproductive outcomes. From this angle, understanding predictors of social estrangements is critical to understanding factors that affect human welfare and mental health.
Based on the current research by Sung et al. (2021), borderline tendencies emerged as a large and significant predictor of the number of estrangements in one’s life. These findings have important implications for the understanding of borderline personality disorder as well as our understanding of the role of social estrangements in understanding mental health.
Social estrangements have the capacity to wreak havoc at the individual and community levels. For this reason, humans evolved to be highly sensitive to issues surrounding estrangements (see Geher et al., 2019). Understanding predictors of social estrangements helps with understanding the emotional factors that underlie mental health as a whole.
In a new study, Sung et al. (2021) found that among a suite of personality traits, borderline tendencies were substantially and significantly predictive of the number of estrangements in one’s life.
Maybe those with borderline personality traits could benefit, then, from better understanding the adverse nature of estrangements when it comes to well-being. Perhaps such an understanding could lead to helpful self-insights that might have future social and emotional benefits.