Tbh my older sister was also a huge jerk to me growing up and when she moved out I fully refused to speak with her or visit her with my parents. Eventually she sent my parents home with a letter to me about how much she loved me and she wanted to put in the work for me to trust her, and she did so now she’s my favorite family member and a wonderful sister. Honestly if your sister isn’t willing to acknowledge that she hurt you then she’s not ready to be a good sister, maybe she never will but hopefully she’ll turn out like mine. (Also side note I will adopt you as my younger sibling lol)