I know I arrive late here and you probably already said everything there is to say, but I would like to throw out my feelings about this matter. I watched the film in 2006 and I did like it, but it didn't really affect me. That would come a couple of years later, as I found myself in a better place in my life. Then it got me, like a punch in the face. I read the story too fast the first time, as I always do, and read it again real slowly going over every word many times, English not being my mother tongue, it's not an easy one to read. And I love both of them equally and different. What lacks in one is in the other. I don't know if it makes sense. For instance, I have read many posts stating that Ennis is more open about his feelings in the book, but I think those words are translated into expressions in the movie. That little fond smile when they are riding back from untangling the sheep, the dozy embrace and the scene after the divorce. That look on Ennis haunts me, when he says "You know I am sorry", all Ennis is there, IMO. The inner conflict, the inability to express himself, all he is trying to say to Jack with that look. "You know I am so sorry, you know I would love you to stay, you know what I feel for you, but you know it's not possible. You know what I feel for you, you do. Don't you?"
Those things are obviously not in the book, but there we get Ennis' words instead.
That is why I think it is somehow unfair to compare book and movie, they are just different languages.
Funny thing, I have read the short story again, but I haven't been able to watch the whole movie again. I can't watch after the fight scene, I just don't want Ennis to get that f**** last postcard. I'm thinking about watching the film with my girl, she's 13, and I hope I keep it together until the end.