Why do we think we are broken?

A deep vein winds through human thinking that we are somehow damaged or broken, cut off from something God-given and elementally pure. Whether we are or not is not a question I know how to approach, and yet I find the idea strangely and darkly appealing.

Cultures rooted in Christianity are versed in this myth. We became conscious, self-aware humans through the Fall. Nietzsche felt it. Freud saw it, too. In a critique of de Waal’s views on the origins of morality, Christine Korsgaard writes

human beings seem psychologically damaged, in ways that suggest some deep break with nature. (emaphsis mine)

Why do we have this perception of being broken? Does it only come out as we attempt many a metaphysical backflip, swamped in our own self-evaluation and -doubt? Or is it a daily habit?

Why do we see consciousness as such a burden?