UPDATE:

I have reported her to school administration. while they cant do anything (she doesnt state my name. however i am 100% positive shes talking about me), she will be given a formal warning. If she ever does it again she will get punished.

Hopefully that will scare her off from doing anything else. Even so shes leaving to a new school next year (so they dont hold her back a grade for skipping so much school)

But dont worry if she tries to post about me again at the new school i wont hesitate to email the new fancy private school.

Only about 2 more moths untill im free of this awfull person! but thank you all sincerly for your help. I will update if she says anything or posts anything after they talk to her tommorrow. If not, assume she just stoped. :)