The berries?

Am I missing something here? It seemed like this movie was trying to be artistic and thought provoking but I'm really confused on some things.

One, I thought it was weird that the time she decides to record whats happening the guy just sleeps. But I guess I get that, the time he was with her before it seemed like he just wanted a hot female to sleep with like he used to. I also read some thing someone else posted about it being a weird hospice thing, which I also kind of understand.

The thing I don't get at all is where she gets into the car and has a handful of red berries then just drops them on the floor before she gets to the house. Is this in part of the book or something or was it just totally random? Any bit of information on this would be greatly appreciated because this is the kind of *beep* that will drive me crazy!