The Eye of Night by Pauline J. Alama
"I'd seen nothing in the still pool they call the Mirror of St. Fiern, nothing: not even my own reflection, for rainstorms had drowned the pool in dull, blackish mud. That featureless blackness, more than any evil vision I might have seen, seemed to pass a death sentence over me: my life was a void, a starless night. For a moment, I felt I must cast myself into the depths and drown, as though the saint herself had urged it. I'd never felt less inclined to return to the Order, but neither had I any glimmer of a new life outside it."