On December 1, 1963, Jacqueline Kennedy returned to the White House to begin the sad task of sorting through the clothes and belongings of her recently deceased husband, President John F. Kennedy. White House staffers openly wept as they helped her, but Jackie refused to give in to tears.

“We’ll cry later when we’re alone,” she once told her assistant. Jackie was not wrong. Over the next years, the traumatized widow would be haunted by recurrent nightmares and experience bouts of heavy drinking and suicidal thoughts.

“In the spring of 1964, she actually thought about ending her life,” Paul Brandus, author of the new book Jackie: Her Transformation From First Lady to Jackie O, exclusively tells Closer Weekly. “She was miserable for quite a long time.”

Jackie, then 34, and the couple’s children — son John F. Kennedy Jr. and daughter Caroline Kennedy — moved into a stately home in Washington, D.C.’s Georgetown neighborhood. But unfortunately, it brought her no peace.

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“Can anyone understand how it is to have lived in the White House and then, suddenly, to be living alone as the president’s widow?” Jackie has said. Following the president’s assassination, she used to obsess over what she could have done differently to save her husband’s life in Dallas.

“She could not stop thinking about it. She had nightmares during the day,” Brandus tells Closer. “And going to sleep brought her no rest.”

Many nights, she closed herself in her bedroom, crying and self-medicating with vodka. “I think God’s unjust now,” she once said, telling Father McSorley, a priest brother-in-law Robert Kennedy introduced to her, that she longed for death. “Do you think God would separate me from my husband if I killed myself?” she asked.

Jackie was unable to put aside her thoughts of dying. “The term PTSD did not exist back then, but clearly she was traumatized,” says Brandus.

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Jackie’s children gave her a reason to rise every morning, although at times she thought Caroline and John would be better off living with Robert and his wife, Ethel. “I’m no good to them. I’m so bleeding inside,” she told the priest.

Yet she tried. She threw John-John a belated 3rd birthday party. She had the children’s new bedrooms painted the exact shade they had been in the White House. At Christmas, she hung stockings in front of the fireplace and took a family trip to Palm Beach, Florida.

“Her love for her children gave her strength,” says Brandus, who notes Jackie had always treated motherhood as her most important duty. “She said at one point that if you do a poor job of raising your children, then nothing else you do in life really matters. She lived up to that,” he insists to Closer. “They always came first.”

In the fall of 1964, Jackie left Washington and moved with the children to New York. “She was always a New Yorker first,” says Brandus, who reveals that Jackie gradually began cultivating friendships with other celebrities who shunned the spotlight like Greta Garbo. “She sent Jackie a very warm letter after she moved to New York,” the author dishes. “They had dinner from time to time.”

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Jackie also appreciated having younger sister Lee Radziwill a few blocks away. It was Lee who had introduced Jackie to Greek shipping magnate Aristotle Onassis several years earlier.

Jackie’s marriage to Onassis, who was 23 years her senior, in 1968 would shock many, but it offered her the peace of mind she was missing since Jack’s death. “Jackie didn’t believe the Secret Service could protect anybody — especially after the assassination of Bobby,” says Brandus. “Whatever doubts she had about Onassis, they were outweighed by what he had to offer — first and foremost security.”

Onassis, with his enormous wealth, a private island, his own airline and armed guards, made her feel safe. “He rescued me,” said Jackie, who died at age 64 in May 1994. “At a moment when my life was engulfed in shadows.”

For more on Jackie and her family, pick up the latest issue of Closer Weekly, on newsstands now — and be sure to sign up for our newsletter for more exclusive news!

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