Alford knows that readers may judge her harshly; "it doesn't frighten me," she said.
She describes Kennedy as "a kind and thoughtful man." And then, she tells stories of what she calls his darker side.
She says Kennedy once asked her to "take care of" his aide Dave Powers, who had served as the go-between facilitating the affair; she performed oral sex on Powers while Kennedy watched. The president later apologized to both of them.
On another occasion, she wrote, he asked her to do the same for his brother Teddy. She refused.
Then there was a party with a "fast Hollywood crowd" at Bing Crosby's house in Palm Springs, Calif., that she attended with the president. A guest offered yellow pills that she believed were poppers, or amyl nitrate, a drug often used to enhance sexual pleasure.
Kennedy asked her if she wanted to try one and she said no, but she said he popped the capsule and held it under her nose anyway.
"Within minutes of inhaling the powder, my heart started racing and my hands began to tremble," she writes. "This was a new sensation, and it frightened me. I panicked and ran crying from the room, praying that it would end soon."
Alford debated whether to share episodes like this, taking them out of the book and putting them back in. If she had excluded them, she said, "it would have felt like I was not telling the whole story."
When the affair with Kennedy was revealed in 2003 — the Daily News of New York published her name — Alford spent a few days holed up in her apartment with the media camped outside. Then they left and she started going to work and going grocery shopping again.
After interviews to promote "Once Upon a Secret," she expects to return to her quiet life once more.
"It's sort of like closing a chapter on that 18 months," she said, "and closing a chapter on keeping secrets."
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