Please don't hurt yourself. You are young and like Shy said, you need to seek counseling. That could change your whole outlook on life. It isn't too late for you.
I think also as Shy said, you could get it all out about the abuse and deal with it now so you don't have to go through life later with dealing with post traumatic stress disorder or the awful nightmares. Please listen to Shy and get some help soon.
In the meantime we are here for you. Keep posting as maybe we could have some other good ideas to help you. A lot of us have gone through the same thing you are going through.
Alcohol and drugs only suppress everything and it just builds up inside and surfaces later. There is no other way than talking about this to get it out now so that you can continue on with your life.
Just remember that we are here for you.