Sometimes we need to express ourselves out loud. As long as you know that it is imaginary I don't see any harm in it. Ok some people may think it weird, but really is it any different than me talking to my dogs while I am on a walk. They don't really understand my vocabulary either but they do connect emotionally. I often pray out loud when I am alone as well.
We learn and experience things through a variety of avenues, i.e. writing, speaking, reading, visually etc. Verbalizing your thoughts and feelings is a very helpful tool. I find that when I am depressed (unfortunately rather frequent these days) there is a lot of solace and I gain a certain objectivity this way. I would not worry about it as long as one is not delusional. To heck with what others think