My stepmom is moving out w/ my little sisters.. the kids are already gone b/cuz she wants time to pack or.....

whatever so they are staying at the new place w/ their aunt.. they left tonite & my s-mom says she never wants me to see or contact them again.. i feel so horrible & can't calm down about it.. how can i chill out & what should i do about my situation?? i don't even know where to begin about trying to get visitation rights.. she is just doing this b/cuz her and i don't get along so she is trying to make me miserable by keeping the kids from me.. and it's beyond the point of talking..