Alright highschool life, help?

Sooooo We my friends and I, were friends with this girl, but then she started hanging out with the "older, cooler kids" seniors and ****. so now she acts better than us, and is ALWAYS taalking ****. she even went so far as to spread rumors, and now she like changes her stories and stuff if we ask her about it. it's so Redic. but anyways... what should i do? should i confront her, or do i let it be as i have been?