I won't write a long post, because I think you've been given really great suggestions from people more experienced and wiser than I am. I know the abrupt advice sometimes hurts, but it helps too and in my experience what is hardest to hear is often the thing we most need to pay attention to.
What I would ask you to think about is the fact that he says he is working on getting his mother to change her mind about you. You've mentioned this a couple of times as a sign of a positive change. To me, there is another way of looking at this. You are his wife. In an ideal world his mother's opinion of you shouldn't matter (unless you are abusive and she is telling him you are, or something like that...) His loyalty needs to be with you. He needs to be on your side, and more interested in getting you to like his mother, rather than the other way around...
It still speaks to me that his priorities are wrong and that you're accepting crumbs. I agree with you it is good to look for the baby steps and be positive about them. But it is also important not to lose sight of the bigger picture.
