Been ENM with my (36m) wife (40f) for over a decade. We’ve had our ups and downs but generally it’s been great. 

We have our rules, the most fundamental one being that even in the context of ENM, we would always operate on a bedrock foundation of mutual respect for each other and each other’s partners. We never got hung up on the “not in our bed” nonsense. If my wife has a date, I’d rather she be in her own space where she feels safe and in control, and where she knows I have access in case anything goes wrong. We both take partners back to our home regularly - we have no kids so there’s no problem there. 

We had agreed that if one of us gets home and the other is there with a partner, then we don’t disturb the date and just wait until it’s over. We’ve also always gotten off on listening in on each other when this happens, which anyone we bring back home is made fully aware of. Usually we all have a drink together afterwards.  

I got to my house and she was there with her longest-term partner, who has been in our lives for about 6 years at this point. They didn’t know I was in the house and I started listening from the landing -  they were talking about me in an incredibly humiliating way. He would give her prompts, asking her questions about how pathetic and useless I am, and she would agree, about how I can’t fuck and am a shit husband and she would agree and pile on with name-calling and degrading comments about me.

FWIW I know it’s part of a power/humiliation dynamic, but I don't care. I was fucking furious. It’s not an ego thing, I know I’m a good attentive husband and if I can allow myself a moment of conceit, I’m a pretty damn good lay as well. I would not EVER tolerate any partner of mine saying a bad word about my wife, and I would die before I participate in anything that humiliates her even if she’s not there. At no point in our ENM journey did I consent to become the object of my wife’s derision and disrespect when she’s on a date, especially with her closest and longest-running partner.

I walked into the bedroom (big no-no) and told him to get the fuck out. My wife was livid and said no he’s not going anywhere, but I put my foot down and kicked him out of the house. We had a massive fight, she told me I was being a huge pussy, I told her she doesn't respect me, and some harsh words were said from both sides.

That was Tuesday night and we haven't really spoken since (I certainly won’t be the first to make contact) and she’s been staying at his place all week, which is a mmaajjoorr violation of our ground rules but I also broke them by kicking him out. For 13 years I've worshipped the ground she walks on, and I refuse to accept the way they talk about me, even in the heat of the moment. It's not right and I won't stand for it. 

It's really put the future of our marriage into question, because I won't move forward with him still in the picture and that will cause a volcanic amount of friction (she really likes him and has known him for almost half the time she’s known me), it would severely disrupt our system and I know she would resent me for it, but I also know I will resent her if he stays. 

I feel steadfast in this, but I'd appreciate a sanity check before I make any drastic moves.