I was in a sexless M. I didn't cheat. I was almost at the point of filing, though. Being in a sexless, or almost sexless, M is grounds for D. File and free both of you. He needs to be with someone who wants more sex and has a broken moral compass. You need to be with someone who is both compatible with your moral values and with less of a sex drive. Let him go. If she knew he was married,she deserves him.
ETA: Ultimatums don't give extra time. Imagine giving your kids a week to finally comply with your ultimatums. They would laugh and then continue because they knew they got away with the behaviors. Also, you should never deal with a cheater from a point of fear. Contact the other betrayed spouse. If that has him dumping you and running off with her, he was going to do that anyway. Better to pull the plug now. In reality, most of the time, because they're living in a fantasy, it bursts the fantasy bubble. It often forces them to finally pull their head out of their asses. Like I said, though, if it doesn't, best to rip the bandaid off.
[This message edited by StillLivin at 10:49 PM, Friday, February 7th]