Exactly Ken... You don't press for D... Leave your wife to do all that work and do NOT encourage her.
Just sit back and leave it alone. Your wife is going to probably try initially to pursue divorce to see if you pick up on it and help her along.
Your wife's going to be in a lot of pain soon if OM leaves finally and she lets go of that nonsense at last... Withdrawal can be quite painful and she will very likely think Divorce will end all that... It won't... It's her pain as a result of HER choices.
Just do your own thing and walk away when she talks divorce. If she wants to be honest about OM and cry on your shoulder you listen but don't hold her hand or any of that crap. Its GOOD for her to open up to you about her affair, this is how you two will bond again... But you can't get sucked into it Ken... you need to stay DETACHED and in control... Your wife is NOT running this marriage right now YOU are and that's how it SHOULD be until your wife is educated to make healthy choices for herself and her whole family... She's a walking hand grenade right now and shouldn't be making any of her decisions.
Just keep doin what you're doin.. Protecting your family, speaking up about the OM to everyone, and protesting your wife's treatment of her home and family...