Moonglow: A Novel by Michael Chabon:
My grandfather often felt frustrated or baffled by my grandmother’s illness, but when it came to the origins of the Skinless Horse he though he understood. The Skinless Horse was a creature sworn to pursue my grandmother no matter where she went on the face of the globe, whispering to her in the foulest terms of her crimes and the blackness of her soul. There was a voice like that in everyone’s head, he figured; in my grandmother’s case it was just a matter of degree. You could almost see the Skinless Horse as a clever adaptation, a strategy for survival evolved by a proven survivor. If you kept the voice inside your head, the way most people did, there could really be only one way to silence it. He admired the defiance, the refusal to surrender, involuntary but implicit in the act of moving that reproachful whisperer to a shadowy corner of a room, an iron furnace in a cellar, the branches of a grand old tree.