Wow. So, this thread proved amusing on a late night with nothing to do. I lol'd. A lot.
Anyway, some suggested changing friends, etc... yea, I don't think you should have to go through all the trouble of changing friends and acting fake to get her away. That would be a suckish waste of time, effort, etc. Really, I'm not sure what advice to give. Since I wouldn't actually know just how severe it is. But from a blunt point of view, just ignore her. Let her get bored with herself or whatnot. And, when she does something that can't be ignored (like if you walk outside and she's at your doorstep), confront her. With the door thing though, you could always just walk back in and slam the door in her face as well. Anyway, you don't seem to have much backbone really. Backing down time and time again because she's scary, etc etc? And since 7th grade? You should have stopped it so much sooner. With some of what you do, from her odd perspective she probably thinks you like it all. Why, I wouldn't know. But whatever. Oh, as well, if she's like a really crazy psycho person that starts to change, get aggressive, and snap on you.. yea, don't get yourself (or anyone) killed, first off. But keep evidence, and do two things: one, go to the cops. two, commit her to a psychiatric ward. I would hope your troubles wouldn't go that far though.