Could 'D' be one of Chance's split personalities?
Not sure why, but I'm thinking there's going to be some sort of mind-screw twist. Here's my guess as to what it could be:
Chance has multiple personalities, and 'D' and possibly Jaclyn are those personalities manifested.
I had a buddy suggest it recently so I haven't been able to watch closely to dispute it. And something about it rang strangely true for some reason. The whole thing about D not being able to drive (hmmm?) and Jaclyn's whole weird situation in general.
I'm sure I'm probably wrong but wanted to see what people think the big twisty-twist could wind up being.