Daddy dearest is off to Disney World with 2 babies his OW's son fathered with 2 different women with whom he has no relationship yet his own kids probably see him for a total of app 6 hours a year. Never an overnight or vacation since he left. Told D (she turns 25 while he is away) that he's not sure when he will see her for her birthday.
But the kids know that Mom is always there for them. They are also working hard to pay their own way in life (which is a really good thing to learn). They appreciate the things they have - they've earned them.
It took me a long, long time to pay little attention to him and what he and she do. They are broken people. They deserve each other.
You are doing well with a man who seems so good for you. ENJOY! Forget the ex!