Terrible Tide — Charlotte MacLeod

Cliff House may be haunted, but no ghost is as scary as the family's secret history.
Holly Howe is just beginning to succeed in the cutthroat world of New York modeling when a car accident ruins her good looks forever and she is forced to retreat to the backwoods of Canada, to recuperate in her brother's ramshackle country house. But Howe Hill is a wreck - dusty, ugly, and utterly lacking in modern facilities - and her brother is no more hospitable. So when Holly hears of a job in town taking care of Mrs. Partlett, an elderly, widowed invalid, she leaps at the opportunity. If nothing else, the Partlett mansion must have indoor plumbing.
But Holly soon finds that while Cliff House is eerie by day, it's terrifying by night. The other housekeeper is convinced it's haunted by the ghost of Mr. Partlett, but Holly fears no poltergeist. It's the old widow in the upstairs room that frightens her - and the secrets that lurk behind her dull, silver eyes.