They will never have a family. That's the first thing. Families are not born from ugliness and pain. I don't care how many rules they shove down their throats, those kids know the difference.
The second thing is that they are totally and completely full of shit. They are false. As we Italians like to say, they are nothing but a "fugasi".
The problem here is that your asshole ex brought the kids around OW and married her very quickly after your D. That means they haven't had time yet for the cracks in the foundation to come to light. Don't worry, they will.
I felt a lot of pain over this stuff too. It didn't necessarily involve my kids because ex couldn't bring the slunt around them for a while. But, I'm in a small community here and slunt has a big mouth so I heard about all sorts of shit that he never did with me that he decided to do with her. I'm talking exotic vacations, sports and activities, etc. Like you, I thought, "who the hell is this guy??". And, like you may be thinking at times, I thought she just must be better than me for him to make such a change.
Now? That is all a crock of shit. Nearly three years later, a common household and a total of four kids EOW, those cracks in their foundation are shining through like a m-ER f-ER.
There are no more exotic vacations. Slunt doesn't brag about sexy time anymore. It's clear that the kids drive her nuts and that his true personality and habits, which are all out there now, drives her nuts. She yells at him on the regular and uses his weakness to try to force him to discipline our kids the same as hers, and to essentially throw her kids into the forefront. She is jealous and horribly insecure. He has to be glued to her hip or she pitches a fit. They have almost no money and he lost his reputation and whatever respect his friends, family and co workers had for him. He now isolates with a few trashy people that she hangs out with.
Oh sure, they try to put on a show with the kids every once in a while with their ridiculous rules and goofy ass "traditions", but again, it's all fake. Nothing but smoke and mirrors. If she could have him back where he was - in secret A mode with full access to my salary, she would. I guarantee that.
Trust me, my friend, these leopards never change their spots. He will try to keep up with her demands and rules for as long as he can stand it. Once he's had it, this stepford wife, Brady bunch, we're all perfect parents crap will stop. Its inevitable. The time just hasn't passed enough in your case for reality to truly sink in. It will and then you will see that he didn't make a drastic departure from who he really is - he just covered himself up for a while.