I think it's wrong. Similar to what meander said, there is a commitment and if things are working then going outside of the marriage only complicates things. They should be in counseling to see if it can be fixed. The woman might have medical reasons for part of her issue but there are other ways to try to satsify your partner.

Most likely if he is going outside of the marriage he has not told her. That means if he does that to her there is a high likelyhood that he may have other partners that he doesn't tell this woman he is having an affair with.

Tranquility