I saw this film this afternoon. I think it's a brilliant film. Ian McEwan portrays a young man who is indoctrinated by his religious parents who finally glimpses another world. Emma Thompson introduces him to poetry and the idea there's a big world out there, bigger than his tin-pot religion.
It reminded me of Willy Russell's Educating Rita. That scene in the pub after she's been studying Shakespeare and she thinks Lady Macbeth is a cow. Her husband and family are having fun in the pub and she just feels lost. She's glimpsed another world, she doesn't fit in there and she's doesn't fit in with her tutor's friends so when he invites her around for dinner she doesn't go.
This is the problem. You grow up in this religious world, you look down on scientists, academics, literature, everything really. Then you find yourself in the world and at first you feel lost. I think that's what McEwan was trying to show in the film. When people leave a cult they have nowhere to go and they feel totally lost.
I read the book and saw the film and I don't think Adam went back to the religion, I think he refused treatment, effectively took his own life because he felt lost in the real world and couldn't cope with the fact that his parents would have let him die. I think he was depressed and suicidal.
Good book, good film by one of my favourite authors and an atheist who is trying to get the word out about religion and how it damages people.