I believe Dylan and her interaction with him wasn't real. When she ''wakes up'' she sees everyone just there. They're not talking to each other, they're not interacting. I believe that Dylan was created by Robin.
I know this doesn't change the story but I just needed to say it. It's just my own interpretation anyway.
I just got done watching this movie. I think it may have been a shared hallucination up to a certain extant. This is the future, and who knows really how advanced this chemical technology is. When Dylan takes her to the big city for the first time he explains how the world has changed. He tells her that while people are consuming their new identities, the people put pheremones off into the air that your mind "translates into an image". So there may be some kind of advanced chemical communication going on with the help of this super advanced chemical technology.
And as an afterthought, I would think he had to be real because then how can we explain her magically acquiring the drug that would cleanse her mind of all that junk