When I was 13 I watched the film adaptation with my parents and was heavenly shocked by the story. I had always heard that heaven was a wonderful place, and this version seemed to be really confrontational. Showing you everything you lost and everyone's trouble you caused.
But it made me want to read the book as well. And though I already knew the story I really liked the book. The way it was written just fitted the story and the context. I was a little bit older when I read the book, and everything seemed to be more in place now. It's a wonderful book I would love to recommend to everyone!
Note: This was one of the first books I read in English, back in 2008; Nowadays I mostly read English books.