Leave yo ex the hell alone. He is your ex for a reason. Unless y'all have a mutual agreement that y'all are working on it - LET HIM GO
Stop trying to sabotage his new relationships. Popping up at family functions and shit
Stop leading yo ex on. There’s probably a reason she acting crazy as hell. (1) she for real crazy (2) you entertaining the shit which is giving her a reason to think y'all bout to get back together.