I've gone through this with my sister. =D
Years ago my sister(four years older than me) did the exact same thing to me. The awesome thing about it was that I had a lock on my bedroom door and she didn't have one on hers, so I took it upon myself to ban her from my room. We often bickered, still, but atleast she wasn't invading my "territory". Afterall, we had totally different styles and tastes in music. She was an all A student, and I always made C's & D's(Its still that way! ). Overall, we just didn't clash. We just learned to keep our distance from eachother.

Ever since my sister got out of highschool, we have become best friends. She acts just as immature as me at times. Her group of friends and mine hang out all the time, almost every afternoon. I know my sister doesn't like some bands I listen to, and I don't like some of the stuff she listens to. We just hold our tongues and get over it.

Haha, so i guess what I'm trying to say is to just hold it out. Keep your distance & get to a point where your sister can't get under your skin. Don't let her know that what she does gets you mad. =D
(((hugs))) Sisters can be sucha big pain sometimes.