Looks like you have major trust issues. Luckily, trust is not a very important factor in marriage. Marriage is about home ownership and being able to tell society you're not single. Why can't the four of you just go out together?

So many levels of disfunction here. First, you have a "friend" of the opposite sex who you think you should be trusted to hang out with but you don't think your husband is trustworthy enough to be allowed the same with his "friend" of the opposite sex. See a problem? Now granted hubby was once in a relationship with his "friend", obviously it ended ok as they are still "friends" but did they continue sleeping together after breaking up? Has he been unfaithful in any other way? What about you and your "friend"? Any feelings there? Have you ever done anything that could be considered "romantic"? Emotionally charged Kiss that "just happened because you were upset", drunken sex that "will never happen again", even half naked back rubs? Many relationships start with "friends". Taking your post as exactly as you wrote it your asking him to trust you while saying you don't trust him. Ever notice many cheaters accuse others of cheating to sooth their own conscious? By saying he can't see his "friend" but still insisting on seeing yours you put that concern into his head. If you can't trust him for a good reason and think it's odd that that feeling would be reciprocated you need couples counseling. If there is a reason then you need couples counseling and if that's not an option you should probably break up now rather then wait till you blow up.

Your husband is an idiot. It would be justified if ur best friend was ur ex

Hey gal, you can't have 2 bananas in front of you while he only has 1 cat to play with. You got to learn to be fair

how has this not been an issue before you got married? it sounds like something that should have been worked out before the wedding bells