Guys, Men of GAG, what would you do if your girlfriend/wife asked for or demanded an open marriage/relationship?

Just curious, i asked because a friend of mine had this happen to him. He agreed to it, and when she found out that he found someone that was better than her in every way possible she demanded they close their marriage. He declined and divorced her, marrying the other woman.

Personally if my wife demanded this of me, she would be out of my home in 24 hours. I wouldn't even give her an answer, the moment she left the locks would be changed, and every last bit of her stuff would be on the front lawn, with the divorce papers. Open marriage = failed marriage = one partner (who ever suggested it) just wanting permission to cheat guilt free.

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3 mo
There's nothing "evolved", "mature", or "enlightened" about an open relationship, it's simple hedonism, its primal pleasure seeking behavior. And after, when it doesn't work there's no going back.
Guys, Men of GAG, what would you do if your girlfriend/wife asked for or demanded an open marriage/relationship?
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