If you think a warning is unfair, you can PM a mod about it.
Anyways, I've seen a lot of problematic people in my life of any orientation. It has nothing to do with their orientation, but with their personalities and the groups they're hanging out with. I tend to avoid groups and try to connect with others on a personal level. Because of this I don't have many friends, but it does allow me to bond better with the friends I do make.
Of course, this might not work for you. But what I do recommend is that when you want to make friends with someone or get into a group, you look at how they are. Either as group or as individual. Sure, some might seem nice initially and then turn out to be bad. And good friends can change into bad friends. You always have that risk, no matter if they're straight, gay, bi, ace or whatever.