Ever since I watched Grave of the Fireflies back when I was a teenager, I felt a great deal of disgust towards the brother character. How could a brother let such a thing happen to his sister? I couldn't appreciate Grave as a film, and I still wouldn't watch it again. To me, his actions were inexcusable. Besides which, I felt it was an exercise in bathos. Researching it a little today, however, I found this interview with Hayao Miyazaki regarding his interpretation of the film. Basically, "I think it's a terrifying movie which depicted deaths without a place to return to." In context (of the article and the war), it's quite interesting what he has to say.
Takahata himself also had a couple of things to say about Grave. While what he said has bearing on real world issues, I really don't think it adds anything to the story. What's worse is that it sounds like that was central to the film.
Grave is also based on a true story, sadly enough. One thing I thought about was how it was that a growing boy could survive the malnutrition that his much younger sister could not. There is the obvious answer which the author confirms. He hates himself (or he did), and that's good enough for me. I don't know, I'd like to think I'd do better in a situation like that, but who can say for sure?
As a story, I found it trite and disgusting. As a semi-autobiography, I found it sad and deplorable.