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Fear of Abandonment and Borderline Personality Disorder (BPD) loom larger than gains, meaning that people by nature are aversive to losses. Loss aversion in behavioral economics refers to a phenomenon where a real or potential loss is perceived by individuals as psychologically or emotionally more severe than an equivalent gain. For instance, the pain of losing $100 is often far greater than the joy gained in finding the same amount.

How about in relationships, loss of a partner is more intense than the joy of having them close. Loss aversion gets stronger as the stakes of a gamble or choice grow larger. Prospect theory and utility theory follow and allow the person to feel regret and anticipated disappointment for that said gamble, which BPD turn on you. This causes a spin, perhaps a downward spiral.