Infidelity Support Group
Any relationship in which one partner engages willfully in sexual relations with another outside of the partnership is considered to have experienced infidelity. This breach of trust is often traumatizing for the faithful partner as well as the relationship, and support is often needed to heal emotionally and to decide whether or not the relationship should continue after...

You may have to force his hand a little though, and one way of doing that is to have your wife tell him that you are about to contact his wife. Whatever he tells his wife is really nobody's business. Let her hear it from the horse's mouth. And for all we know she could be having an affair as well.
This woman is worth the time and trouble of you going to jail? - wow, she must be one hell of a woman.
I would never put my freedom or safety on the line for anyone, but that's just me.
These days with the amount of lunatics walking out there, I am not sure if opening this type of can of worms is a good idea anymore.
You describe that you have tons of communication between them - that makes me think that your wife is the one you need to figure out if you should be with. Outsiders aren't your problem, is the person you life with. JMO