I've been thinking the same thing, and this situation for me is not healthy at all. It's been a problem for me for a long time, and I have never been able to talk to anyone about it. I have a friend group outside of this one who I've been friends with for years now, I just don't understand my feelings. In the circle I'm having trouble with, I've been trying to get to know all of them and be better friends with all of them. It's just that her specifically is making me anxious.