I'm not single. I'm a woman, even. And I have the exact same theory as he does. I expect to be able to be friends with whomever the hell I like, and my husband has the same. I don't have to spend time around his friends if I don't want to, and the same for him.

I have a good enough relationship that we can both express distrust for the friend, but that isn't something binding or obligatory to follow. If I find myself jealous, that is a problem I need to overcome and not take out on him and I expect him to do the same. I don't have reasons not to trust him, and if one doesn't trust their spouse, perhaps they should address that issue.

I'd not enter into a long-term relationship thinking this wasn't the case, honestly.