Hi, the sentence is usually " I don't want anything to do with you." As others have said, it means that the person does not want any contact with you at all.

when you say "I don't have anything to do with..." it means that you're not involved with something or someone. ex: "I don't have anything to do with that incident" = "I'm not involved with that incident." however, "I don't have anything to do with you." could mean: "I don't have any business / connections with you." or in a rude manner, "I don't care about you." :)

maybe it means that you dont care to him/her cowboy...

It might mean as well " i don't know you"

I guess it means:"we have no relationship."or" it is none of your business." And you can also say it in this way"i have nothing to do with you"