Hi JavaJoeToes,
I'm so sorry you are going through this while you're pregnant. You sound like a tough lady and I wish you all the extra strength you need to get through this.
IMO, I think a lot can happen within a years time. Maybe he goes to addiction therapy and realizes he has a problem, maybe he doesn't. Maybe he decides he wants AA and sobriety. Spending a year away from his family might make him do some soul searching, and honestly decide he wants to be better. I wouldn't count on any of these things happening, but sometimes a drastic measure, like you moving out, is the knock on the head someone needs to wake the heck up. I would stay right where you are, AWAY, for now. Maybe reassess the situation, his progress, and your feelings in a year.
And as far as him living in the driveway.....no way! That is NOT respecting your need for space. That is him trying to manipulate you. I can't even list the problems I fore see happening as a result. Eeeesh!
Best of luck to you, and keep us all posted. We're rooting for you!