I've been really impressed with much of the thinking you've done, about how to incorporate Love & Stosny's ideas into how you conduct yourself in your marriage, about increasing self-control, about your mind overhaul, etc. It's wonderful to see a stronger you showing through.
With respect to how your H suddenly became withdrawn and silent--try not to dwell too much on why, because that's all speculation and mindreading. By all means, note the change, note the connection to an earlier situation in your M, but then let it go and focus on what you can know: yourself. Whether he's feeling shame and guilt (and it seems to me a bit early in the game for him to be dealing with these issues yet) is really up to him to resolve.
I found that, from the start of the MLC till he reached Acceptance, my H was very angry at my family. Much of the time he spoke disrespectfully and critically about them, he was irritated by having to spend time with them and unpleasant afterwards ... but this was only a part of holding his own family, family of origin, and close friends at arm's length (or, of being too depressed to be able to connect effectively with them). Once he left MLC, all this gradually disappeared, and he was warm and delighted with my family again. I don't think he really remembers being otherwise, so try not to focus on it too much.
As you practice compassion, try not to think of your H as uncaring or selfish, but more as being stretched to the limit of his endurance, so that he has no care or attention left to give to anyone else. And keep thanking him for the the kindnesses he shows, because that genuine praise will make him feel better about himself.
