"She was someone who heard each grain in the hour-glass, she ..." — Rupert Thomson quote meaning

She was someone who heard each grain in the hour-glass, she felt the passing seconds like sandpaper against her softest skin. Time actually seemed to hurt her, and people helped her get through it. [..] Sometimes it seemed to Nathan that her life was just that, a feat of held breath, just another ten seconds, just another five, and then death would flood her lungs like water, a string of glass bubbles to the surface and then nothing. She was scared in a way that he could understand. The kind of fear that sends you running across a six-lane highway or jumping into rapids. She was someone who ran towards her fear, screaming. Who tried to frighten it. Who, in another period of history, would have been worshipped as a saint or burned as a witch.