Living in the American South's Bible Belt, I am deeply familiar with the kind of intense religious bombardment the protagonist experienced -- it's pretty much par for the course for any place or subculture where religious fundies have a grip.
I thought the movie did an EXCELLENT job of portraying this aspect of the film. I thought maybe mother was a WEE bit over the top hateful and intrusive, not that I don't believe mothers like her exist, but that I think the filmmaker missed a big chance of portraying the way kindness can also be used as a tool for psychological manipulation.
The part the filmmaker UTTERLY screwed up was helping us understand the reason for the protagonist's rebellion. Was it adolescent angst, a healthy sexuality growing and rebelling against the repression, or just a healthy human response to the general repressiveness of evangelical beliefs? We have no idea, because the idiot filmmaker just gave us lots of shots of the lead actress looking sullen instead of any meaningful dialog that would have helped us UNDERSTAND the reason for all the sullenness. Of course, there was a lot of dialog with other young people on her blog that MIGHT have been illuminating, but it wasn't. It was just the usual shallow talk of normal teens about sex.
I was hoping for more depth, more insight, than a teen might have about the issues raised in the movie. I didn't get that. A shame, because without it, the movie is a real nothingburger.