Black-and-white thinking, also known as splitting, is a common characteristic of Borderline Personality Disorder. It involves seeing situations and people in extreme terms, often based on perceived "good" or "bad" evaluations, Alternately idealizing or devaluing individuals or situations can lead to intense emotional difficulties in relationships.

Black-and-white thinking can also affect self perception. Individuals with BPD may see themselves as either perfect or terrible, leading to difficulty in maintaining a stable sense of self.

Essentially, anything that evokes strong emotions can trigger black-and-white thinking including a serious stressor, like being separated from a loved one, or a seemingly minor stressor, like making a wrong turn.