I think, when we are completely honest, we will admit to acting as though we are internally communicating with something that we don't talk to like it's just some internal dialogue with ourselves. What that means about the universe is pretty wide open, but the fact that we all do it seems worth noting.
Like you, I also don't believe that anything exists outside of existence to violate all of the laws of existence.
For lack of a better way to describe it, I think reality is the body of God. The closer we get to understanding reality, the closer we get to God. We are all a part of reality, & some sort of product of evolution, so I suspect there is some good reason for the way we talk to ourselves. Whether there is actually some sort of "super consciousness" or whether it's just our conscious selves talking to our subconscious selves is hard to really say.
For all we know, since we are a part of reality (God), maybe our subconscious is some sort of connection to God. It is at least our connection to all of the older preverbal systems that ultimately evolved & grew to form us.