Sending my prayers to you in this hard situation. Addicts normally don't treat others very well because the disease has them focused on their drug of choice. I agree with jnj - it is important that you take care of yourself.
A good way to start is to find a Nar Anon family group. That support (and posting here) can help you sort things out.
It's easy to say "just leave", and hard to do. And we always hold out hope. I've found it is just plain difficult to know what to do to help the addict - and in the meantime we forget about helping ourselves.
Prayers that you find a way to care for yourself no matter which decision you make - and prayers for clarity in making your decision.