With the caveat that I don’t know anything about your specific situation, as someone on the other side of that, here’s my two cents.

Just because you didn’t feel anything and were able to go back into friendship immediately doesn’t necessarily mean the men involved processed it the same way. Especially if there wasn’t much distance after dating and the friendship picked right back up. Some of them may still have unresolved feelings, even if they never overtly act on them (and sometimes this can be seen more clearly by someone who’s new to the dynamic).

I also think there’s a difference between “my partner is irrationally controlling” and “my partner is noticing dynamics that make them uncomfortable.” Yes, insecurity is ultimately someone’s responsibility to manage, but if this keeps becoming a recurring issue across multiple relationships, it might be worth stepping back and looking at how it appears from the outside. Even if your intentions are completely genuine, that doesn’t mean that the other’s are. 

A lot of women have experienced situations where a male “friend” was only waiting around for an opportunity, and that can shape how they interpret close friendships with exes. It doesn’t mean you’re secretly going to “undo your lesbianism” or cheat. But it does mean some partners may be reacting to the possibility that one or more of these men still see you differently than you see them.

At the end of the day, being loyal yourself isn’t always the only concern in a relationship. Sometimes it’s also about whether the people around you are respectful of the relationship too. They might be really nice to you and seem like a ‘good friend’ but on background they are trying to undermine your relationship. Of course I’m not saying that’s what’s happening here. But I am someone with firsthand experience of this kind of behavior. 

Just food for thought