I agree with you in part that cutting off relations is the best approach, but there is a risk, and while many have recovered their marriages, many others have pushed it right off the cliff. It feels good for a while to say you did the right thing and the spouse was wrong to continue the affair, but D is still D. If she can cut off the relationship cold turkey, then great, but so far I don’t see signs of that. I think what you have done so far is the right thing. I just think going forward you need to re-evaluate.
She is still in the house with you. You are still married. Counseling can still fix this marriage, even if she has some contact with the OM. There are lots of couples who have been able to do just this, so don’t think that having her cut off relations entirely is the only path. Is see her hanging on to the OM as not just an addiction, but as a safe haven away from you. Forcing her to cut of the affair might work, it might not. Things might not change until the stakes are so high and the damage so severe that she capitulates or walks. Those are not the kind of probabilities I would want to stake my recovery on. She is addicted because of her fear, and breaking this kind of addiction can be a gradual process.
I'm not proposing in any way that you ease her guilt, but she has to have something positive to work toward. And contrary to your comment OTB, I do think Choc has a LOT to prove to Mrs.Choc. There is no way she can be solely faulted for the withholding that occurred in the marriage. Both of them did their own withholding. She is trying to state this. How much truth there is in her version is debatable, but that does not really matter. If she believes it, she believes it, and she must be validated. Other wise she will seek validation elsewhere. Just be careful.
