I have read about this and think It describes me, should I see a doctor or therapist? I have suffered from depression and mild agoraphobia since my teenage years, I am now 26. I change from periods of feeling happy and content, to feeling suicidal. These changes can happen from one day to the next. My mood changes are extreme and can be very hard for my partner to live with. One characteristic that made me think of Borderline personality disorder is the way I react if someone close to me leaves or has to cancel plans etc. If my partner has to go away for some reason I completely break down and start assuming that he just does it because he doesn't want to be around me. If he is late to pick me up from work I get so angry for no reason. If a friend cancels plans on me I get over the top angry and then start beleiving they hate me and are trying to get away from me (when in reality they had been called into work!) I can change from raging angry to crying and sobbing within minutes. I feel like I cannot even predict my own behavior or control it. Funnily enough if somebody else is down or needs help I am right there, as the voice of reason and support. Is anybody else like this???