[Telybell]

First of all, I'm sorry this happened to you. Being victimized in such a way must be a horrible experience.

Now as for what you can do:
A lot of people told you to think about therapy. I second that, it can really help you come to terms with what happened to you. There are even therapists specialized in helping victims of abuse.
A lot of people also told you to talk to the cops. Well, you can do that, if you feel up to it. It may or may not help anyone. I think you might also consider ganging up with some reliable friends, maybe also some of his other victims, and make his life a living hell. This could mean outing him to his community (maybe he goes to church? is active in a club or team? the people there can be contacted), making sure everyone knows what kind of person he is. It could also mean terrorizing him verbally (anonymous phone calls, emails, letters) or physically (spray painting his walls, delivering poop to his doormat - there's even an online service for that - throwing in his windows). Even retribution like beating him up is a possibility, but be aware of your own safety as well as legal ramifications.

I wish you the best of luck in recovering from this traumatic experience.