I think fini's advice is good. I come from similar family dynamics as you describe and I still to this day have trouble asking straightforward questions. My default is to wonder, engage in lots of conjecture, and try to figure out what I believe to be cryptic messages or thinly veiled rejections from family members.
What if you did ask him if he blames you for your mothers death? Or if he resents you being married or being sober? I know it may not even be possible to have an open and productive dialogue when it's never been that way with you guys, but it's worth a try? I'm practicing this in my own life. It's hard because it's not a natural way of communicating for me in close interpersonal relationships where I feel vulnerable. My family was full of guessing, wondering, assigning meaning, being defensive, and telling each other how we felt.