In one way it's good that the other guy is so disruptive. Your wife can see who he really is without the veneer. Guilt only works when you're desperately unhappy, feel alone and think you're worthless. If she knows you have her back, then the siren song that once worked becomes a mosquito whine.
Also, being the one to extricate herself, to take ownership of the cleanup has to give her confidence, a sense of proving to herself where her commitment rests. She is earning her freedom from the other guy, her reconnection to you.. building rather than tearing things apart.
