A couple of things here OP.
He’s 56, and has a 5&2 year old. This made me nearly pee my pants in laughter. He will be knackered.
All his mates will be playing golf, going to concerts, going away for the weekend, and having post kiddie fun. Your ex has to do the weekly shop and probably all other chores.
New wife is 19 years younger and from Asia. Newish to the UK.
I actually lived in Asia for 17 years, and I hate to say this, but there are a large number of ladies from certain countries who will go after someone older, for their money, get a few DC under their belt, then use them as their cash cow. I’ve even heard some use the phrase “milk the cow dead”. What’s more is, your older white guy, is perceived to be loaded, and his £ is fair game to the whole of their extended family. This is all a well known fact to anyone who has lived in Asia.
Your ex had his head turned by someone 19 years younger, who may have used every trick in the book to hook him. He’ll be onto DC no3 pretty soon. I bet she gives him unbelievable amounts of shit for having given you or your DC any money.
Basically he’s fucking miserable and probably living in hell. It’s not about you, but he took it out on you because he thinks he still has a connection to you via the DC. In his head, you may still be his wife.
The best revenge is to live well. Don’t worry about weddings as she’ll never let him go. He’ll be working till he’s 70, but tbh I doubt he’ll make it to that.
You are well rid of him. Keep his toxic shit away from you. Don’t acknowledge him in future, but do make sure you always look fabulous when visiting that supermarket, and you’ve always got a bottle of something sparkling on top of your trolley to rub salt into his wounds.