Oh my God, I’m so sorry this has happened.

Here’s a thought: Did he know before you did that they were swingers? Maybe his best friend talked about it from way before, and DH was already excited and half brain-washed? Or, maybe he told them that he would do it if you said “Yes”. Maybe he truly believed you’d be an easy sell??

Only because for him to go on and on about it for ten months?? And you’re the one with the problem??

Also, how old is he? This sounds like mid-life crisis with emphasis on the crisis.

I think all you can do is wait it out. He hasn’t done anything, but has gone temporarily insane. I would wait for the spell to be over. Think of it as a secret shadow side that popped out like a bad zit. Hopefully it’s over.