need confirmation

[heartz2488]

My mother is very emotionally abusive although I do not feel she is aware of it for many reasons. She subconciously surrounds herself in drama and it seems about 90% of the time her relationship with usually just one but sometimes multiple person/people is in turmoil. If she is mad at my stepfather then she is very nice to me and everyone else. Here since I have gotten older her emotional battle is usually taken out on me. I am now in college and trying to start my own life, but she knows just what to say or do to make me feel bad about decisions I make. I do not drink or do drugs, I am either at work or school. She knows I am a "good girl" and says so all the time, yet she is hardest on me. She has horrible relationships with her mother and father (although the issues are unrelated) and it seems when everything is going good emotionally she has to do something to mess it up. She is a drama queen and can say horrible things at times. Even when I was little I can remember her telling me that she was leaving us, or wanted us to all move away, or she wanted to commit suicide. I do not feel she is suicidal because my mother will do anything for attention. She has always told me to leave and get out, and I have a few times although she always uses guilt to get me back. I love her and I am always feeling bad. She makes me feel like I am a bad person all the time because I spend most of my time with my best friend and her family but I sometimes I get depressed if I stay home too long. She has been divorced twice and is now in a relationship again. My sister who is 13 recently left to live with my dad because she couldnt take it anymore. She blames the way she acts on things that have happened in the past such as the two times my father tried to seek custody of us. She has complicated our lives by her choices. My sister is only my half sister, she told my father she was not his, however he was willing to accept that and not get a divorce. She put his name on the birth certificate and then later divorced him for my sister's father. Now they are also divorced and my sister is force to have "2 dads." She is 13. Last time she told me to get out I refused (because she says that all the time), so she called the police. I was unaware she had done this and before they called me downstairs she had talked to them for about 10 minutes. We had been fighting because I had taken up for her boyfriend when she said something horrible to him. She told the police I chased her around and tried to beat her. When I came downstairs I was hysterical. The policeman screamed at me and threatened to arrest me. I did not know what to do. I am not that kind of person and he would not let me say a word. She was being so sweet to me. She called me by my nickname and the tone of voice she was using was so sweet is was sickening. She lies about situations and things she says. She exaggerates what others say to her. She will not admit to anything she does/says. She projects her actions/emotions on others. It is stressful and it takes a toll on me mentally and physically. I can not lose weight and I am a frequent eater. I have thrown up since I was 7 years old. Noone knows about this. Everyone thinks I am this strong individual who helps everyone and is kind of a clown, yet I have so many bitter feelings. I am a psychology student and I feel she has borderline personality disorder. She has an amazing personality and is so fun to be around but she is also the worst person to be around. I am not sure if I am correct in my diagnosis, but she sometimes stays in bed and is openly depressed. Other times she is fearless. She talks down about herself all the time, and talks down about others as well. One of my psychology professors advised me to move out, however I do not have the means to do so as of now (she kind of made sure of that). I just dont know how to help this situation if she will not even admit anything is wrong. I have talked until I was blue in the face and so have others but there is always a fight. Is my diagnosis correct and how can this be resolved?