How do you continue when you are completely apathetic?

Yes I am depressed. (For the record I hate listing my problems, but when I don't, everybody underestimates the stress I have gone through. So lets begin) I was born dead and 2 months early. My mother didn't take care of herself while pregnant. She then abused me until she was arrested for trying to kill my family. Then my father tried divorcing her and I was forced for 10 years to go to visitation with a psycho. She was granted all sorts of payments because the judge pitied her. So my father was working hard and had no spending money. My grandmother who was like my mother died abruptly of cancer. 6 months later I was diagnosed with cancer. I fought off cancer for 2 years and had part of my leg removed. 2 years later, my father was diagnosed with cancer, and he died. So at 16 I became an orphan with my brother and sister. My mother 2 days after my fathers death sued my for half a million dollars claiming that my inheritance was hers. I sank into heavier depression and was suicidal. Then I was sent to a lock down treatment center. They didn't know how to treat my depression and instead tried brainwashing me for 8 months. I got off all medications that were documented not to have any effect and sought to find my own path. Had to make Then my sister filed a restrain order against my uncle who was acting as my caretaker until the legal guardian came under. After persistently trying hard in high school, I graduated with an 3.8 GPA. My twin brother nonetheless got into Cornell, and I was rejected. I have been at this other college and have been doing miserably. I have no friends, I rarely leave my room. I don't get my work done, but still pulling off B+ average. Before it got bad I sent out transfer applications trying desperately to get out of here. I just got rejected from a school that I was accepted last year. This was my safety school.Whats funny is I was thinking about suicide 2 days ago, and didn't do it because i thought well I have next year to start over. Now I have to decide to stay at a school that is horrible, or drop out of college. Either way, my life is going to be nonstop depression. My whole life everyone has pitied me. I am the strain on everyone that knows me. I hate this. I hate myself, i hate my life, i hate everything. Everyone knows that my twin brother is the only thing keeping me alive. But, i'm causing him stress. He just told me that he tries so hard to makeup for my father and to take care of me. even with him im just a charity case and and stress. I supply no happiness no positive to anyone. They only care for me because I've gotten close with them and if i go that makes the vulnerable. so now im just a vulnerability. I HATE THIS !