I believe that honesty is the best policy. Especially when coupled with tactfulness. I'd attempt to bring it up with a 'I've been feeling that when we are together, you aren't really with me, you don't want to be with me, you are thinking about other things." Let her think about it and possibly respond. Perhaps ask her "what is going on or changed
for you?"

Then that is what you tell her. "I feel a little let down and hurt by you.....". Get it out in the open. Let her respond. She might be sorry. She might not be. You may consider that it is time to move on.
Better off to know.

I'd sit down and tell her how you feel then gauge her reaction and based on that decide whether to keep her as a friend..people should add to your life not take from it..

Why exactly to you need to hang out with her? Can't you imagine life without her in it? I know losing friends isn't nice, but at times, walking away from toxic people is best thing you can do for yourself.

I would advise you not to contact her until she herself tries to make contact with you.

The sad thing is that after all this nastiness you still want to call this person your friend.

I have some insecurity issues, and the way she is behaving is making me feel very down myself. Every time I do see her, I get some gut instinct something is not right..like she is being false in some way.

I was thinking she might be after your boyfriend. Dump here like a hot potato she is not your friend.

Obviously she's not a good friend and is only interested in your BF. She's not your friend.. You should cut her out of your life. She's up to no good.