"The Cell" - Killer's background?

There were some scenes in “The Cell” that seemed to be meant to explain how the killer got the way he did, but like so much of the movie, they were rather incomprehensible.

Were we really meant to believe that as a kid, the guy’s father kept a blow-up doll in the living room? And, if so, that this contributed to the kid’s pathology? Or was the doll meant to represent a real person?

I think it was more that the father beat the hell out him on a regular basis and brutally abused him because the kid was playing with dolls. But it’s been a while since I saw it… I don’t remember a blowup doll, but it was probably trying to show when he started viewing women as things. Just a guess.