He sounds like he's really really circling the drain - I guess you're seeing what happens when someone who blames other people or other things finally has no choice but to look inwards. He can't blame you for his unhappiness any more, and sooner or later he isn't going to be able to blame his job either. I feel sorry for him - and I think you're right to be concerned about his odd behaviour and also right to detach yourself from it and protect yourself and your kids as much as you can.
