This is not a question that can be answered by anyone but the person in question. It's easy to say tough things and make absolute statements about the cheater and about these sorts of situations in general. But nobody but those directly involved know every detail of the relationship and the situation. There are no absolutes here, and it's almost never a "simple" situation IMO/IME. Best not to generalize, and not to speak in absolutes, about other people's relationships. Best to just keep your damned mouth shut if it's not you. Don't offer advice or opinions, just sympathy. Sure, you'll have opinions, but they aren't meaningful or helpful to anyone else in that situation. If you must offer any advice at all, simply refer them to a marriage and family counselor, so they can figure it out with a professional.