For now, go to counselling by yourself. Do it and soon. It will help to get all of this off your chest.
You have already told her what the deal is... affair = it's not going to work between you guys. She has got to let OM go. If she doesn't, too bad, so sad for her.
When she finally decides what's more important to her, if it's you, then bring up the MC.
Is she still in constant contact with OM? What does his wife say?
