Hi Blue Bird ~ I used to do this when I was upset with someone. I would have these conversations, pretending what I would say to them if they were there. I know it's different from what you're describing, but in a way it's similar. A couple of times I got caught doing it, and I felt like a fool.
My friend, I think you should have your doctor refer you to a good therapist. I don't think you're crazy or anything -- don't get THAT idea, for heavens sakes! I just think that, like many of us, you may have some issues that are coming out this way. Many of us have things that are bothering us, but they manifest themselves in strange ways -- ways that sometimes we have no control over or that we don't understand.

This may have to do with some issue you have that you don't even KNOW about!
So have your doctor refer you to a therapist. I'm sure the therapist can help you deal with this and probably get rid of. I wish you the very best, my friend. God bless and please take care! Hugs, Lee