There are a lot of outcasts in the movie, and a lot of people being cast out. Karen, the teacher, is cast out of the school because of her teaching methods. Cherita, as Ada pointed out, is often alone and left out. And then there is Roberta Sparrow, the town eccentric, and of course, Donnie himself.
These outcasts made me think, once again, about truth, and here, about how you have to go off the beaten path to find it. Like with the white rabbit from Alice in Wonderland (as Julie G. mentioned), or, more specifically, in The Matrix. There, Neo also has to choose to follow the rabbit, in order to fulfill his destiny, just as Donnie follows Frank, seeks out Roberta, and learns the "cellar door" from Karen. It reminded something that Roberta said to Donnie: "Every living thing dies alone". Everyone’s going to have to go off the main path for the big choices – and Donnie is no exception. In truth, Donnie did die alone.
Julie’s blog also made me think about destroying and creating, and about how much power being a destroyer/creator allows a person. Donnie is given enormous power in the movie – he burns down houses and shoots people in the head. Yet, he also sacrifices himself so that other can live. If this last sacrifice is his destiny, I’m wondering if a destiny is a destiny if one chooses it (I think one of the characters in the movie talks about this). The word seems to indicate that one is pulled to such a place irrevocably, and if that is true, then there really is no choice. How much choice do you really have in your own destiny?
I like what you’re saying about whether it was Donnie’s “destiny” to die, or if he made his own destiny, and then is it even considered destiny anymore, and on and on until your brain starts pounding. I thought about the same thing, and remember when Donnie tells his psychologist that he doesn’t believe in God? He says that he can’t imagine there being a God who lets people die alone. His whole Frank/Time Travel forced-destiny removed God entirely from the lives he effected. Almost as if he could prove that God didn’t exist since he could create his own destiny. And did Donnie really die alone? He is laughing when he goes to bed, almost as if he is fully aware of what he’s done and what’s about to happen. So physically he was alone, but did he feel alone, since he was dying for Gretchen to live, and so on? I don’t have any conclusions on all that, I just thought I’d add the God element to your destiny question. :)