My friend talks about me

Don't worry what she says about you. Don't ruin a good friendship over this (if it is a good friendship, examin why you're friends, know yourself, figure out if she's the kind of person you want to associate with). Though, expect friends to do this anyway. Good natured ribbing. Don't let it get you down. If she seems to be shunning you from the group, you can always befriend someone else in the group as a more secure anchor. Be open to all options before you start closing any doors.

Confrontation, mental suicide - I hear that.

I wouldnt be so worried about what she's saying. Most likely she's just really self-conscience about herself so she's making other people see the flaws in you and nnot focus on her own. That doesnt really sound like a very healthy friendship though. So just look at the situation and if she's worth staying friends with, then stick it out. If you decide she isnt, dont be mean to her or anything, just dont hang out with her as much, cause you dont want to be around someone who thinks you're boring or whatever. That's not fun for either of you. And never change the person you are for someone else either, you'll just eventually hate the person you become. Hope that helps.
-A

If you feel you should confront her, do so infront of the friends she has been talking to about you.

If they know you know she has no way out and no option to admit, apologise and stop.

If she were to blow up and get pissy then she's really not worth having as a friend in the first place.

This has happened to me before. I confronted my friend with the problem and she admitted that she never was my true friend and I got over it...but it still pains me to know that she spread horrible rumors about me