Vulnerable is definitely the right word. It's the most open that the poetry feels -- the most compelling. Because for once it feels like Eliot's baring his soul to us, the readers, even if he isn't.

I can't think of anything worse than being alone, but I don't think it works as Hell from a Christian standpoint...if Hell is the absence of God, that means there's somewhere God *can't* be, and yet he's supposed to be omnipresent. This is one of the things that makes me discount the idea of there ever being a hell. Dante invented most of it -- why not give him the credit for all of it? I don't believe a loving deity could condemn anyone to such torture for eternity.