okay so basically, my mom has this boyfriend and i was really okay with him at first. he was funny and he made my mom happy but it turned sour after his mom died (keep up with me bc there's a lot)

So my mom, C, and her boyfriend, S, got serious around the beginning of 2021. S had went to jail for something that wasn't his fault but he took the fall for it. so during the summer of 2022, my mom had made a girl friend, C2, and when S got out, they all quickly formed a three way relationship. It was revealed later on that C2 was very toxic and manipulated and tried to get my mom out the picture and have S all for himself. Ofc, they ended the three way and now it was just my mom and S.

Fast forward and S mom had passed away around Aug-Oct 2022 This is where S kinda starts being a dick.

He was still texting C2 even when my mom said not to but C2 wasn't the only one he had been texting. there were and still are multiple. He started doing cocaine and even gave him up his 50% rights to his truck to a drug dealer but only if he doesn't have to pay for the cocaine. He started to isolate my mom, accusing her of cheating whenever she picked up and bc of this, she never really did. They have broken up three times a month and each time he comes back, but not before he harasses her, threatens her, stalks her and makes her feel unsafe to the point where she doesn't wanna be at home by herself.

Basically, what im saying is. I know my mom is going through a very draining and very toxic relationship and i have seen it all. the cheating, the having multiple girls in my moms bed/car. ive seen everything. and im so tired of seeing it. its not even my relationship yet i feel like im a part of it and its mentally draining me. i told her today, since he come back, that i think i should finish the last 5 weeks of my senior year staying with my granny bc tbh, im not comfortable having him there. she thinks im joking but im dead serious. So WIBTA if i left?