I agree with you Snodderly - one of the striking things about my recent interactions with my xh is his politeness and hesitancy. He hasn't been doing the cuckoo clock bird flying out.
He actually said he quite understood if I didn't want to talk to him or meet him, which suggested to me that at least a glimmer of light has entered his fuddled brain. He equally hasn't said he was sorry, but he did come up with a sizeable chunk of money to help with youngest son's law school expenses. I do think the magnitude of what he has lost is coming back to him - he said he hoped to have the opportunity to get to know his sons' wives and partners better too But didn't blame his children or their partners for this, as in the past. .
One thing I do belive is that those guys who run fast hard and for a long time, do really terrible things to their families, afer a lifetime of 'good behaviour' genuinely can't see a road back that they can take. Not my problem, and nothing I can do, but I do feel sorry for the terrible mess he made for all of us. We are OK now. He at least seems to grasp he was part of the mess, that it didn't just 'happen' and that we have all moved.