Just don't go back.
AndroidBoy: Three choices--Stay with him no matter what he does to you.
Don't like that do ya?
Try these. Resolve not to date anybody for a few months. Learn to exist as your own person. Examine why you keep going back, then address that. Or you can find a new guy. If you really don't want to go back, then try burning bridges. How does that work you ask? Date his best friend, and be sure to talk about how great he is in comparison to the loser you keep going back to.