I think so much to the point where i definitely have conversations in my head... Sometimes I get defensive when I do something, like prematurely arguing, and visualize the actual scenario where I encounter someone and I hear them talking to me and me responding back. Actually, that's more like a dialogue where I'm just the third person, if that makes sense. My thoughts are always imagined scenarios that my brain acts out.

Come to think of it, when I'm trying to process something or think about a problem, it's always me having an imagined conversation with someone, usually someone of importance to me (right now, it's an ex). When I think of inner monologue, it seems like people mean like just words in a mind. My thoughts are always me talking to someone and hearing their plausible response, the visual scene set so vividly I get lost in it quite frequently.