Get that good ending gurl

mousy mouse girl realises that her bestie cinderella is not happy in her marriage with her trash prince husband. So her last wish was to save her, and the hot cursed/sick "fairy godmother" reincarnates her 15 years in the past so she can save her loved one, and maybe also the sick/cursed/poisoned(?) wizard

she's so tired from dying 99 times for other people, of sacrificing her life for the greater good, that she stops expecting good things to happen since all of her earlier lives were upsetting (shit parents, backstabbing friends, plots against her, etc.).
But her family is great this time! And there might be another reincarnator with her?
But that annoying white kid in her dreams starts using her powers against her family. They'll probably become allies but he sucks fr.
Just let them be

bestie died and wants to get revenge on all the bitches that bullied her at her school, and her husband (+royal family) that betrayed her, and her "family" that used her to marry her off to the prince only to kill her later.
She's a smart cookie, her revenge will be fun!

strong dark female lead! reborn in the psycho family of the book's "bad guys", she tries to survive her crazy dangerous family members and to help the good characters so she doesn't get executed in the end. all for the good ending!