For me there’s two separate participants, a ‘talker’ and a ‘listener’. My mind identifies more with the talker, because that’s the one that has agency. Since there are two participants, both of which are me, I talk in 1st person plural (‘we’ve got to do …’, 'we thought about this earlier’). I stopped being afraid of being alone after I started having an internal dialogue around the age of 11, since having a second participant in the conversation meant I was always in company.
My base thoughts are non-verbal. Sometimes I describe it like shapes in a hyperdimensional vector space.
My internal monologue is basically just practicing translating these base thoughts into language, to explain concepts to others.
This analogy started to feel particularly accurate for my own experience when I started learning a second language. I realised that I wasn’t learning what one word meant in another language, but instead, attaching the two words to a deeper idea/concept. It means that I’d often understand what I was hearing, but even when I was listening in my new language, I didn’t automatically have the translation to my native language (English).
And my thoughts/internal experience is like that. I can pull the words out to describe the thing, but the actual thought itself, the concept that I’m using the word to describe is where I would say my thoughts naturally sit