Why would a guy you like push another guy on you when you done told him over and over it's not going to happen?

This guy , I know we are trying again as friend's well I thought we were. But he keeps wanting to piss me off with this. He insist on this other guy on me when I told him over and over. I don't won't him or want anything with him or be friend's. He did me wrong in the past I have no news for him. But this guy seems to push him on me. Why does he? I thought he wanted us to actly try. But I see he don't. He keeps bringing this other guy up. I done wrote and told him to shut up about that guy. That I don't won't him and never have. Why is he insisting I want him when in hell I don't won't the other guy? I asked him to shut up and don't bring him up but keeps on. How do I get him to stop and shut up about the other guy ? He did me wrong and his girlfriend. They stole things from me in the past and everything else. I done told this guy that I'm not talking or seeing or nothing them. I told him nicely to stop. But he won't. This what happened last time. He think he can have rules on me. But in hell he can't. We aren't together never was. We aren't married. But he insist going to stay in the past. How do I tell him nicely what I think of him and all of them? I thought he wanted to try guess I was stupid and blind with feelings for the guy. He never will change. He is the one in the past I moved on. But I'm the type of person I give some ppl chances. But if you steal from me then you cross the line. So how would you go about telling his guy what you truely think about the other? I done told him and told him no not doing that. But he keeps insisting I am. Told him to shut up. Told him that he is bringing the past up and staying there. I once did. It's all him. He think I'm doing that when I damn ain't. So please if you can please help me out. How to tell this guy what I truely think of him and all of it ? How to tell him why bring up the past? Guess he will never change and never come out of the past. If you help I'll help you. Thanks again.