I've seen where birds of a feather flock together and so forth, but I've also seen cases in which it would be a grave error to assume a person is like their friends. I have been thinking over this question, and I think what I'd like to see is that the person is consistent.
If she plays at being a woman of upstanding character, but then acts like her friends who aren't of upstanding character because she's around them, that's a red flag. If she maintains her character regardless of who she's around, that's a good sign.
I don't think people act perfectly consistent in every aspect of their lives, from what I've seen. My sense of humor isn't sinful (99.99...% of the time), but it does lean toward more adult aspects of life. It makes sense to censor that around my 2-year old niece, and my dad, who is very straight-laced. It's not that they're ignorant of my humor--okay, maybe my niece is--but my dad at least doesn't appreciate it.
Consequently, I expect some variation in a person, but if they lie to one group to cover their actions with another, or show any kind of truly two-faced behavior, that's going to pluck my feathers. It's not so much their friends who are important, but who they are when they're with their friends, and without them.
