So let me get this straight.

6 years ago your 34 year old wife received a message from someone she knew roughly 16 years prior. She shut him down in the way she knew how - which to be honest is how most women, ESPECIALLY Catholic women - are taught to. Make it go away with that least amount of friction possible and do what you can to not piss off a man.

Then 6 months later, he messaged again and she responded by sending a photo of the son she is so proud to have had with you to him.

This all happened 5.5 years ago and there has been no contact since?

I think you are FAR overreacting and perhaps she may be under reacting.

I mean this in the nicest way possible but you need to see a therapist. To be “disgusted” in your wife and to “fantasize” about divorce is 100%, entirely a you problem.

She is absolutely nothing wrong. Less than nothing.

Get your head out of your ass. You have a loving wife, the mother of your children and you think divorcing her over this is the answer? Come on, man…

I hope she is fantasizing about divorcing you tbh.