I read the book way before the movie came out. So I knew exactly what to expect from the movie. I will tell you that there was somewhat of a big stink because they changed the ending in the movie (like Cookie, the end of the book caught me off guard). A friend of mine -- who'd also read the book and we went to see the movie together -- sent me an email link to the author's website where she asked people to PLEASE stop emailing her and asking why they'd changed the ending in the movie, she said she'd had no control over it once she'd sold them the rights to the book. We went to the movie well-supplied with Kleenex, we knew what was coming.
I think I ought to add here, that almost always, when I read a book and then see the movie, I'm disappointed in the movie, because the book was so much better when I imagined it in my own head, rather than watching someone else's version of it in a movie. But that wasn't the case this time. The movie was as good as the book, just had a different ending. I think the actresses (and the actor who played the father/husband) did a great job.