I'm sorry things are difficult for you. I would definitely hold off buying a house with someone with whom my relationship was troubling and difficult.
When I got sober first time round I left my husband as our differences were so obvious in the sober light of day and I re-evaluated what I wanted from a relationship.
With regards to intimacy it's important that both parties are happy with what is happening. Whether he is unhappy with lack of frequency or if you are unhappy with him leading to lack of intimacy is something only you know. Is marriage counselling an option? you don't have to settle for an unhealthy unloving relationship which is no good for either of you.
I hope you are able to make decisions about what is best for you.