Man, I cant think of a worse feeling. I am so sorry you have to be the adult. The deal is ADULTS dont go around kickin ass, they find solutions to live with. Juvie wouldnt get you anywhere, and thats the only place violence will take you, it wont solve your problem, although I do understand it may make you feel better at the moment.
I used to be a foster parent and have seen this crap up close and personal, I truly wish you the best.