I'm SICK of my best friend!?

[carlie]

Ok it's like a love/hate relationship at the moment. Sometimes I absolutely love her and I really don't know what I'd do without her, sometimes she really really annoys me. For starters shes really two faced. For instance, I used to be really good friends with these group of guys. Then we drifted apart over an argument. And I used to say to my best mate, ah I hate them, and she was like oh yeah there soo arrogant they annoy me so much, yet when shes in town with them and I'm not there she absolutely LICKS THEIR ASS.
And then whenever I flirt with a guy, she notices and immediately starts flirting with them too. Its annoying as!

We've recently developed the same music taste and clothing taste, so whenever she discovers a "new" band or I do, theres always this tension of knowing that you can never like that band she does or she will consider it copying.

It feels like we're so similar we just clash in every way and i feel like a really need some space.
But I don't know how to get out this close relationship without hurting her feelings or ending it over an argument. I just need some space for a while. What can I do?