Stuttering when by oneself?

Stuttering when by oneself? Much of the familiar lore surrounding stuttering includes the caveat that stuttering only occurs when around other people, and that when alone, language fluency is at its best. But for me, this isn’t the case. In fact, it’s about the same. Talking to myself, to my dog, thinking out loud...the stuttering prevails. Any thoughts? Who else does this happen to?