Very true, but it's not really all that sad or painful to watch.
I'm a tad dissapointed "Plague Dogs" didn't make the list. While "Grave of Fireflies" is indeed very sad, the addest I've seen, in fact, it at least has a couple of nice moments to ease the tension.
The Plauge Dogs has none of that. It's bleak from begining to that soul crushing end. It's very tragic, but not really a tearjerker. I remember what really got me (besides the ending) was Snitter lying in the shed, engangled in the visions in his head and states, "I'm inside my head now. And it's where I should be." You just can't help but agree with him a bit.
I own the DVD (ediited, unfortunately) and so far, I've only been able to see the whole thing once. After managing to see the unedited ending of YouTube, even more so.
A magnificent movie, but it's very hard to watch.