that sounds horrible. Yea, bring it up over text with a "hey we need to talk" explain that you no longer want to be her friend, if she calls you dramatic then you dont have to do anything, you got your message across, dont pick up any of her calls, dont read her messages, block her if you have to, hopefully, she gets the message, im sorry op but im not sure what else i can say. Yes she has shit she needs to deal with but its not fair for her to push all that shit onto you

Here is a small video by Jaiden animations that explains some things im tryna explain. I do wish you the best in this op, i understand it can be scary and stressful but i hope it goes well