The most effective weapon for a rogue roommate is love. It's hard to treat people who treat you like trash with kindness, but if you want to disarm your rogue roommate, treat him right. If perhaps he left his clothes outside to dry and it's about to rain, bring them inside for her. She may never appreciate it or say thank you, but deep down she is shocked and ashamed that after all the bashing she gave you, you still treat her right.
There are times you will have to put your foot down and stick to your guns. For instance, if he insists on kicking you out and hosting a house party that is disturbing, just be adamant and disagree with the whole idea. You have a right the place just as much as he does.
Stay calm, cool and collected. There are times your patience will be tested. He may loose his key door and then "request" yours. Take your key back without causing a scene and insist on him getting his own duplicate.
Value yourself and your own needs, too. Don't rush to please a roommate to avoid a conflict. Don't let your principles and values be changed because you fear how your roommate may sneer at you or tarnish your reputation. Stick to your values and you will realize he will respect you if you are consistent.
There are times where things may get to the extreme and you finally decide "I have had enough," but have self control and don't get into personal confrontation that can result to bloody brawls.