I talk to myself constantly as well. And by constantly I mean all day and night. I often “think out loud” about things I am working or obsessing on, or practice monologues, or pathetic speeches I could make to an old girlfriend, “what a better guy I am now” kind of garbage.
There is another thing I do, which I consider a cross between a verbal stim and repetitive behavior. “Self-echolalia” was one term I used to describe it. I make up an odd phrase, in an alternate voice, usually in an American southern or Texan accent. (No offense to any Southrons here, if I didn’t like the accent I wouldn’t imitate it.) My usual joking around voice sounds a bit like Hank Hill. Out of my ramblings I will take a phrase that makes me laugh, then repeat it. And repeat it I do, sometimes hundreds of times a day. I get addicted to the repetition and it takes forever for the stimulus to fade. Months later, the same phrase can still induce laughter. Currently, there is one phrase I have been repeating for over three months.
Unfortunately, I do sometimes speak my phrases in public, along with thinking out loud. This has caused some weird and uncomfortable moments to happen. There have been times when others are around, such as at work, where suppressing the urge to repeat my phrase became very difficult. In those instances, I have said my phrase under my breath, or even sequestered myself briefly in a closet or restroom so I could say it just once at full volume!