Linda Thompson is speaking out about her relationships with Bruce Jenner, who is now known as Caitlyn Jenner, and Elvis Presley in her new memoir, A Little Thing Called Life.

In the book, Thompson, the mother of Jenner's two sons, Brody and Brandon Jenner, opens up about a shocking conversation she had with Jenner in 1985.

"I am a woman trapped in a man's body," Jenner informed his then-wife, as reported by PEOPLE Magazine on Wednesday.

"'Whoa, Bruce, honey, have you looked in a mirror?' I protested. 'You are the epitome of the ideal man!'" she explained.

"I have lived in the wrong body my whole life. It is a living hell, and I really would like to move forward with the process of becoming a woman," he reportedly replied.

After attempting to mend their marriage with therapy, Thompson hoped Jenner would change his mind, but ultimately, she knew her marriage was over.

"I felt such an obligation to keep Bruce's gender dysphoria his secret that I did not even tell my sons until they were 31 and 29 years old, respectively," Thompson continued. "I wanted them to experience enough life and garner enough knowledge, confidence and compassion to be able to deal with their father's true self."

As for her past romance with Presley, Thompson labeled their relationship "all-encompassing."

"The first year of the four and half we would share, we were together 24 hours a day," she explained, according to a second report by PEOPLE Magazine.

Still, Thompson said, the rock star was "needy" and couldn't "stand to hear about anybody I ever dated."