L M Montgomery, THE BLUE CASTLE, The Author of the Anne Shirley Series

This novel is considered one of L.M. Montgomery's few adult works of fiction, along with A TANGLED WEB, and is the only book she wrote that is entirely set outside of Prince Edward Island.
Valancy Stirling is twenty-nine, unmarried, and has lived her entire life with her gossip-minded family who actively discourage happiness and treat Valancy like a child. When Valancy is diagnosed with a terminal heart ailment, she realizes she has never been happy in her life, and rebels against her family and the colorless life they have imposed on her. She begins by judging them objectively, and worse, telling them exactly what she thinks, causing the Stirling clan to conclude that Valancy has suddenly lost her mind. Valancy decides to move out of her mother's house and take a position as a housekeeper for a friend of hers who is now gravely ill, Cissy Gay. Cissy and Valancy had known each other as children, but Cissy became ostracized from society for having a child out of wedlock, and because of her father, Roaring Abel, and his reckless, sometimes drunken behavior.