Shud i just leave her?

Me and my friends stopped talkin 2 this girl because she was backstabbing us and sayin something 2 me about another girl then goin 2 that girl and talkin about me ( but doin it to most of my friends ) we came into summer blah blah blah and she went 2 russia for a holiday then she came bk today and i was talkin 2 my friend (lets call her sarah) on msn and she told me that (my so called friend, lets call her louise ) louise had come bk from her holiday and was sayin that i was tryin 2 turn everyone against her, so i told sarah to tell louise that i done absoloutly nothin and i wasn't the one who started it, then louise was sayin that the notes that i sed she wrote apparently i forged, but whyy wud i do that i'm not dumb ( on the notes she always wrote about my friends and stuff, basically bitchin about them) then i was like wtf and louise sed why am i swearing :l u think ur big... then she said that i was being rude 2 her cuz my ex dumped me ( I' WAS OVER HIM AGES AGO, so i don't kno why she was sayin it ) i just kept tellin her 2 stop tryin 2 blame me cuz i had done nothin besides not talk 2 her.... shud i just leave her alone or confront her @ skl when we get bk... HELP!!