I type to myself,but that has nothing to do with my NPD. It helps with my depression and memory issues. At least I think that's why I do it. I can't remember right now, I'll get back to you.
As for making and changing avatars... I'm guessing you mean do we make multiple profiles with different avatars so we can talk to ourselves? Ain't nobody got no time for that. We don't require validation from ourselves for ourselves, we need it from others.