Why do I want to cut myself...? HELP PLEASE?

For the past few years some bad things have happened. My dad was sent to the hospital for two years because he had clinical depression, then I found out I had epilepsy and it's been very hard to deal with, after that my sister had a bad head injury, then my brother got hit by a car and barely survived, then I was bullied badly at school and it still haunts me, and recently I was diagnosed with depression. I have no one...seriously NO ONE to talk to besides my family. And I'm home alone right now so I really have no one. My boyfriend and I are pretty close but things have been bad between us for about a week, and now he doesn't even want to talk to me. I feel so hopeless. I was getting so down about things a few minutes ago that I actually took a knife (not that sharp) out of the drawer and used it to put a small slit in my wrist..but it wasn't enough to draw blood. Help me please what can I do?