My silly wife says she's in so much love that she's ready to accept him with a wife and kids.
That statement from your wife is more proof that he is telling her he probably isn't going to leave his wife. If he wasn't telling her that, then she wouldn't be having to tell him she will accept him with a wife and kids...
Work on getting ready to expose. It is your BEST weapon to get this turned around. Don't waste this opportunity by being weak. Get focused on your mission.
