“Next is the baby - and congratulations on your little one. You either need the money or you do not. If you can live without it, then that is the easiest answer for now. You may get away without interference in your life and the child's for a time (depends on the laws where you live). And you can change your mind and claim CMS at any time - at least in the UK.
You dc will have a right to know their Dad. In seven years, or twelve, you may be dealing with a child who wants to know Dad and have a relationship with him. And you will need to deal with all those old feelings of unfairness, because this man will lie to your child, will blame you, etc. Your child's realtionship with him, if any, will be their own.
All steps you take now you will need to one day justify to your dc. So beware of your motivations when you take decisions - your anger is fully justified, but maybe not always helpful to you.
I think contacting his wife was a perfectly fine thing to do - she should know what he did - but it wasn't one that will help you. No worries about that, but from now on take decisions only in the best interests of yourself and your dc.
So keep the receipts, all the communication with him in written form. Someday your mucholder child may need or want to see that.”
This with bells on. Forget the guy; forget his wife. Telling her was a damned if you do, damned if you don’t type of step. She needs to manage the fallout in her own way. After all, on your timeline, you had 6 months between finding out and telling her - not 2 days.
If you can manage without his money, in your shoes, I would do that. Focus on your baby.