I love the book, but its essentially an extended short story, not really a novel. I think this is a rare case where the movie is better than the book.
The movie when it came out, had a huge negative PR campaign against it. It was only mildly successful at the box office and didn't take off until the DVD was released. It should have won multiple awards in retrospect. Ebert panned it completely and Rosie O'Donnell did a whole show on how horrible it was and then gave away the twist ending before it even came out. Looking back it was very strange how it was perceived leading up to its release. None of the criticism was about the performances or the story. The media just didn't like the themes presented in the movie, not exactly what criticism should be based on.