I agree, Laughing - you can't judge anything by what he says when dad is there.
Try to call him at times when you know the ex is at work.
That IS worrisome about him cutting off ties to his friends. Depression? Too painful to be reminded?
And this is almost too weird to think, but - could your H possibly have made threats? Like - come live with me or I'll ruin/hurt/something your mom??? I don't know why, I just keep getting this vibe of your on going and making it look like his choice, but really only doing it to "protect" you. Hope I'm wrong.