As hard as it is, I really suggest talking with your parents. I've been there (just recently actually), but I can say that it does help. If they really care, and don't deny things, they'll want to help.

Talking to them might be really hard, so I suggest doing what I did. Write them a letter about what's going on, and leave it in a place they'll see it. You don't have to be there when they read it, so it's a lot easier.

I'm 17 by the way. So just about your age.

PM me anytime.