What is the name of the book that the wife of C.S. Lewis wrote?

Clive Staples Lewis married Helen Joy Davidman on March 21, 1956. She was in the hospital with bone cancer at the time. It was her second marriage. They remained married until her death in 1960. The story of their marriage and his struggle with her loss was documented in his book, A Grief Observed. After her death, Lewis raised her two sons from her previous marriage.