I need insight into how to keep my sanity while dealing with my boyfriends addiction. Someone please help!?

I found out last August that my boyfriend is a addict. After a loveless marriage I find myself completely in love with this new man. We have been together now for almost three years and cannot find it in me to leave. I am having a hard time believing that he loves me while dealing with this addiction. I feel like I am in a never ending battle with his addiction and my love for him. I guess I thought after the first time I caught him it would all stop. I'm realizing now that this is going to be a long road. Some one please offer some insight on how to stay strong through all this. There are no support groups in my area for partners of addicts and it's hard for my friends to comprehend how to handle this. Help me please!!