physical violence sometimes comes in handy....
i mean, come on... if your parents are not gonna handle it, who else is?
actually, as i'm writing this post, i'm having a brilliant idea...
what if you tell your friends to scare her big time not to touch you again? but that would mean breaking the relationship between you and your sister, and friends interfering in family matters...
well, i dunno... i think you really gotta take it up to someone higher up who can help ya... talk to your parents again about her, really... or jus do the usual-teenage-drama of "you just dont understand me" to your parents and cry... hey, it sounds stupid, but it might work