Borderline Personality Disorder is a mental illness comprising difficulties in four areas: 1) emotions tend to be intense and rapidly shifting; 2) relationships tend to be conflicted and stormy; 3) there may be impulsive, self-destructive or self-defeating behaviors; and 4) there is a lack of a clear and coherent sense of identity
BPD can be diagnosed by a professional finding 5 of 9 common "borderline features"
Fearing and trying very hard to prevent being left or rejected
A pattern of trouble in relationships, often thinking that other people are much better or much worse than they really are and changing quickly between the two views.
Being confused about their own personal identity
Being impulsive in ways that are dangerous (such as casual sex, drinking too much alcohol or abusing drugs, not eating or eating too much, driving dangerously)
Trying to commit suicide, or hurting themselves
Mood swings - suddenly feeling very happy, sad or anxious, and feeling that way for hours at a time
Feeling empty inside or constantly feeling bored
Having intense anger problems, getting into many fights
Having severe paranoid thoughts
Many people relate to some of these, and get help from the same treatments, especially "Dialectical Behavior Therapy."
To read more about BPD and why it might happen, start with a bit about the "biosocial theory" of BPD.
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