Irene: A Designer from the Golden Age of Hollywood: The MGM Years 1942-1949 by Frank Billecci & Lauranne B. Fisher
Unfortunately, her first husband died when he was quite young, and Irene never got over it. She started drinking. Her second husband's affairs didn't help. Working for MGM was stressful, and they treated her very badly in the end.
This book is worth buying for the magnificent costume sketches alone. However, I found the writing a bit dull. There are interesting anecdotes about Katherine Hepburn's bitchiness, Ava Gardner's refusal to wear 19th century underclothes and several other stars. Lucille Ball and Judy Garland are described lovingly.
An interesting website about Irene. Here is my article about Irene. Greg LaVoi has launched a line inspired by Irene: