Cher has claimed then-husband Sonny Bono once cheated on her with his secretary in the mid-1960s.
In a chapter of her new book, titled Cher: The Memoir, Part One, the superstar recounts how she suffered her third miscarriage in 1967 and feared she would never be able to have a baby.
Around the same time, Sonny was working on the script for a movie called Chastity and had hired a "young and blonde" secretary to help with dictation.
However, Cher recalled how she woke up one night and saw "two figures" in the den. She also heard "rustling and whispering".
"At that point I knew something was wrong, but kept walking back toward our bedroom, when I saw the shadowy figures of Sonny helping his new assistant out the front door," she writes, according to an excerpt obtained by People. "It was such a f**king cliché. It broke my heart, but you've got to give him an A for effort."
Cher went on to recount how she was "overloaded with sadness" and set off to stay with her mother.
Yet, Sonny was able to win her back with his "charm" - though he also tried to blame the alleged cheating on the Strong Enough star.
"'I wouldn't have had to look outside our marriage if I was sexually satisfied,' he insisted," the 78-year-old remembers her first husband telling her, adding: "That was such bulls**t, but by the time he'd finished I found myself apologising."
The Sonny & Cher duo welcomed Chastity, now known as Chaz Bono, in 1969. They separated in 1972 and finalised their divorce two years later.
Sonny died after a skiing accident at the age of 62 in 1998.
Meanwhile, Cher also went on to have a second child, son Elijah Blue Allman, with ex-husband Gregg Allman in 1976.
Cher: The Memoir, Part One, which also details the Believe hitmaker's childhood and early success, is now available to purchase.
The second volume is due to be released in 2025.
