That one person you really can't stand, but put up with anyway...

So I have this friend, and I say friend lightly because she has worked her way out of being my friend. She's one of those people who is always around and you just can't seem to get rid of no matter how hard you try. Anyways, this friend just got their license, and now it seem nearly impossible to get rid of her. We all can put up with her for a short while but now that she can follow us everywhere has made things very stressful. We all try very hard not to be rude, or mean to her, but when we try to get away and she shows up at the place we are going, you can hear everyone pulling into the parking lot sigh in unison. I don't know what to do, because for the next few months she will keep finding away to be around, thankfully she is a grade below the rest of us and we can all escape next year. I believe the real problem is that we have all started to mature alot faster than her, and she is still acting like a freshman. The entire situation is stressing me out beyond belief and I don't know what to do because I don't want to be a mean person. I guess until I figure it out I will be desperately waiting it out.