My marriage is not emotionally healthy for me. I can't prove grounds for divorce. What can I do?

I want a divorce. I know my husband is a cheater and a compulsive gambler. I know he is a cheater because he gave me an STD. When I confronted him about it, he said he was not cheating and blamed me. He leaves home, he doesn't call to let me know he's gone or even where he is. He doesn't answer the phone when I call. He is sometimes gone a couple of days. He won't agree to an uncontested divorce. I have no proof of grounds for divorce. The house is in my name. I've been paying the mortgage myself and most of the other bills. This situation depresses me. How do I get out of this marriage?

Read more: My marriage is not emotionally healthy for me. I can't prove grounds for divorce. What can I do?