I have someone in my life who is toxic What should I do

I was gonna ask you a question what should I do about this person in my life I've known this person since I was 6 This person is in my life constantly they don't live with me, they're not my father they're the father of my sister, He's controlling, Has some mental problems, he's trying to kill himself in front of me twice, he's was prison for armory robbery, You're constantly always weasling your way back into my life my mom says she knows that he's not coming back but he keeps coming back and I'm sick and tired of it I may not be the greatest person of all time But I try All he does is stare me down, They've stolen from me in the past, They've done some terrible things to my mom in the past when I was a kid Always making me out to make like a problem or I'm some crackhead or something, They're the type of person to do something for someone only if it benefits them, Yes I've done some terrible things in the past, They've also done some terrible things in the past too as well What should I do and how should I handle this situation going forward ? oh as well I've already made a confession on .