Peace, I periodically come here and was surprised to see your story.
I feel for the kids. Unlike in your situation, my X is not gone. He has improved as a father but still acts put upon to spend some extra time with her (at her request). I have worried that she might get involved with someone who treats her distantly and with some disdain, which is how I felt X treated me.
I have observed other in X's family and note that his brother has a way of remaining distant when people could really use a hand and then popping back into people's lives when he needs or wants something. As my D is his only connection to the younger generation and he has seen her only once, I feel that as she gets older I need to help her understand that you are not under duty to help someone as they get older and start to think about who might take care of them. I might caution similarly with X. At least he has a connection with her but I have already seen him leading on her unreasonably.
M: 16 years Bomb 4/07 OW 20s long gone Divorced 11/09 I remarried New Guy Cooperative r w/X regarding D