I need to know what is borderline personality disorder?

Borderline PD: It's a b cluster personality disorder (dramatic, emotional or erratic). Individuals show marked impulsivity and instability of - mood, interpersonal relationships, and self image. Often seen in young adults, it can be very dangerous as fluctuations of feelings toward others ; self are extreme ; intense. Life is often very difficult for the person ; everyone around them. Love/hate - on/off - yes/no.

Get help: Here is the wiki definition which clearly states the characteristics. http://en.wikipedia.org/wiki/borderline_personality_disorder if you or someone close to you has bpd definitely get some help for yourself. If nothing else you need to strengthen your own support system, caring for someone with bpd is emotionally very difficult. Best.

Borderline: Intense fear of abandonment, being manipulative, impulsivity, a tendency to think of people and things in all good or all bad terms, self mutilating behaviors, drug and alcohol abuse, sexual impulsivity, a profoundly disturb sense of self, and extreme emotional volatility.