Should I avoid her or stick around?

Ok so... I have this friend.... let's call her 'Bella'. I've known her since the 7th grade... we're freshmen now, soon to be sophomores. I don't even know what to call her... I don't know if she's a friend... or an enemy. Honestly, I cannot even see who my true friends are anyhow. Well, Bella is the type of girl who cannot decide who she wants to be. We're all labeled as some sort of person and into some group... She's gone from all country girl to prep, to emo, now she's acting like a bad-a$$ druggie. She's this goody goody blonde girl. She's come to the point where she'd convince people not to talk to me and whenever I'm around her when she's with some guy friends of ours... she puts me down.. acts like I'm weird and gives me these looks that make me feel insecure and I never know what to say so I just stand there as she laughs loudly, making sure everyone hears. I cannot even join in the conversations because she pushes me out... Today we were all in our group... We hang out with a variety of people... I'm mainly friends with the scene kids or skaters... Bella was with me and was talking all about how she "bought weed" from this guy TJ. I honestly am NOT into drugs. And I know Bella isn't either. Her mom is the strictest parent ever. I wouldn't know how Bella would even have the time to do drugs with her mom there every single second. I laughed when I heard her say this... she gave me a death stare because she knew I knew that she was nothing but a poser. She tries to be all bad-a$$... she puts me down for not smoking or skipping classes... Even when she doesn't smoke either. I'm just always insecure around her.... But if I stop being friends with her.. I'll be a nobody... I tried to stop being friends and getting new friends.. but everyone seems to go on her side... and I'm left alone. I wonder what's so great about her... is it her annoying personality? Her blonde hair? What's wrong with me? I feel like an outcast when I'm around her.. and NOT around her. I need advice... am I the only one who has ever felt this way? .... Please help. Thanks.