People of GAG, what would you do if your significant other asked you to let their ex stay over night in your shared home?

In my case, it would never happen. One, my wife knows better than to ask that. She knows the answer would be know followed by divorce papers.

I have a good friend of mine who had this similar question asked by his wife. I told him "ask her how she would feel if one of your ex's wanted to stay the night" of course her response was "oh hell no" and he told her "you have your answer". To which she called him insecure, controlling and abusive.. Suffice it to say, he left the house with his children and is staying several hours from her. And of course I won't tell her where he, and the kids are. And I have it on good authority that he is filing for divorce.
People of GAG, what would you do if your significant other asked you to let their ex stay over night in your shared home?
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