I hear you and agree somewhat, and that it might not play well on film. Still, that's the source material. Just re-read the books, and re-watched all the films. I mean, the book pretty much ends with Harry in deep rage/depression, post Sirius death, (and he's been that same mood the whole book, post Cedric death, and Voldemort's return from "Goblet"), he goes to see Hagrid who says "hi" and starts to give condolences, and Harry more or less is like "fuck off" and walks away mid-sentence before he's even had like 10 seconds to speak. To Hagrid. Like, the kindest/most lovable/loyal person in Hogwarts who is only being nice. Though it makes for a bigger impact when Luna ends up being pretty much the one person who sooves Harry and offers comfort. At least a version of this scene made it into the film, even if Harry isn't angry and mostly just a little somber at that point.
As I said, I like the film, but they did take a lot of liberty with its overall theme and feel. Still, they made a pretty taut, and exciting film out of it.