Some people just don’t get it that there’s no need for all that. You cannot fault him for writing to you though as he replied to your email and you were even upset he didn’t reply. Now you are upset he didn’t congratulate you. Might be tempting to write back asking why is he not congratulating. It’s probably wise to stop communicating all together. One of you has to stop first. Don’t reply if you get more emails.

Now if you had kids, especially minors, you’d have to figure out modes and frequency of communication and remain civil with each other for years to come. But in your case it might be time to stop so you can both move on