What about if I want to evict my roommate because she is not keeping the peace. She causing problems in the house. Do I have to give the deposit back?

You can't just keep the deposit because she's not being nice. If something like carpet or paint had to be replaced because of her, or you had to fix things she'd broke, you'd use the deposits towards that. But you can't just use it for normal wear and tear. And if say you had to repaint the walls because of damage she'd done to them and that cost $50. But her deposit was $200. You don't get to keep the full deposit, just what was needed for the damages.