I think you nailed it in that example! I think the clues are often in his self-talk. He says a lot of things in those parentheses that make me wonder if that is the method the author has used to reveal what is really going on... that kind of subtext (but is actually written).Spot on as always. Is MC giving us a hint here? Perhaps I am reading too much in to it.
In my original playthrough, I had a lot of negative feelings. Almost all of them were connected to those "thoughts." They have me second-guessing my decisions. He remarks about the receipt, Gina (more than once), Donny (more than once depending on player choices), the phone call, and her taking to the idea, just to name a few. Sometimes they are more overt, "Maybe now is not the right time to bring up Tori." Other times and most often, it is like the example you posted.
I keep coming back to the developer's words in JetZ's post, "Has she already lost it and the MC is too late in figuring it out?"
Clearly, I think the answers to those questions are "Yes." I just don't know what it means yet.
There is definitely something to it!