While more and more has come out about JFK’s extramarital affairs in the years following his 1963 assassination, what’s always remained a mystery is how much his wife, Jackie Kennedy, really knew.
“There were many senators and people who worked for the president who were really well aware of the conversations that Jackie had with JFK, in which she made it really clear that she knew what was going on,” Taraborrelli tells PEOPLE. “She wasn’t naïve to it. They did have many conversations about it, and she did tell him that she was sick of it and she didn’t like it.”
In the book, Taraborrelli describes two times when Jackie considered divorcing her husband over his infidelities. But on both occasions, Jackie’s mother, Janet, and sister Lee Radziwill persuaded her to stay in her marriage in spite of JFK’s dalliances with other women.
Jackie first broached the idea to her family in 1956 after giving birth to a stillborn daughter, informally named Arabella. JFK was on a Mediterranean cruise at the time and did not return to his wife’s side after the traumatic birth.
But when a distraught Jackie brought up divorce to her sister, “Lee wasn’t convinced,” Taraborrelli writes. “She said she wished she had a spouse like Jack, someone who would do something big with his life, and by extension, hers. It didn’t matter that Jack was unfaithful.”
“Daddy did it to Mummy and it all worked out,” Lee told Jackie at the time, according to the book.
And even though Jackie’s mother disapproved of her son-in-law’s behavior and infidelities, she felt that was the price Jackie had to pay for marrying a man of power.
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“At one point in the book, Jackie says that she doesn’t know if she trusts Jack,” Taraborrelli says. “And Janet snaps at her, ‘Trust is for the weak.’ “
“I think that really says a lot about the way she lived her life and that she was not willing to give up her power to any man,” the author continues. “She wanted Jackie to just find a way. Her heart went out to her daughter. You can tell she wished things could be different with JFK, but she was of a background where she realized that men of power and influence cheat and certainly the Kennedys do.”
For more on Jackie Kennedy and Lee Radziwill’s relationship, pick up the newest issue of PEOPLE, on newsstands Friday.
“Jackie knew it going into the marriage, and Janet knew it as well,” Taraborrelli says. “They kind of knew what they were getting themselves in for. Then they had to live with it.”
Jackie, Janet and Lee goes on sale Jan. 30.