Does anyone try to totally ignore someone they dislike?

There is someone who I strongly dislike and I even avoid doing things that are caused by the person. I try to do everything as if that person did not exist. For example if I get the idea to do something and I think that I thought of it because of that person, I don't do it because if I did it would be because of them. If they say something that I did not know before, I pretend I never heard it and that I do not know it, and I never use that information until I hear it from someone else or figure it out some other way that I do not believe is caused directly or indirectly by that person. I try to not do anything that I would not do if the person did not exist. Does anyone else do this?