I just ended that game and i quik saved at the end right before gman starts talking to you. So i started a new game and heard his speech at the beginnin and then the end speech a couple of times and it definitely sounds like he completely controls you. It seems like he puts you wherever you go, before you appear in the train he says "its time again" "uve been sleeping at work wake up", and then at the end he says "good job i have many offerts for you that I'll pick". To me it seems that g man controls you, g man might even kind of put u to sleep temporarily until he needs you again preserving freeman from aging too fast.
Also does dr breen die at the end?
Also does dr breen die at the end?