"The General's Wife: The Life of Mrs. Ulysses S. Grant" by Ishbel Ross. My rating: 5 out of 5 stars. Published in 2016.
Book description: An excellent and diligently researched biography of Julia Boggs Dent Grant (1826-1902), the wife of the 18th President of the United States, Ulysses S. Grant, and First Lady of the United States from 1869 to 1877.
Before reading this biography, I read General Grant's two-volume memoir, and I commented that he made very little reference to his wife. That is true, but I totally misjudged his relationship with her, and I'm so glad reading their story has caused me to realize how wrong I was about the character of the man and the quality of their relationship. Their story is a love story.