Marilyn Monroe Confessed to Jackie Kennedy About JFK Affair; First Lady Complained About Sex Life: 'He Just Goes Too Fast and Falls Asleep'

Jackie Kennedy was aware assassinated President John F. Kennedy was having an affair with Marilyn Monroe, because the Hollywood actress confessed to the First Lady.

According to the Daily Mail, a new tell-all book says Marilyn Monroe called Jackie Kennedy at the White House to tell her she was having an affair with her husband, to which the First Lady responded:

"Marilyn, you'll marry Jack, that's great...And you'll move into the White House and you'll assume the responsibilities of first lady, and I'll move out and you'll have all the problems."

The book is titled "These Few Precious Days: The Final Year of Jack with Jackie," and author Christopher Andersen claims Jackie decided to "turn a blind eye" to the Marilyn affair, but it deeply bothered her.

The affair bothered Jackie with good reason; Marilyn wanted to become the President's second wife, according to the Daily Mail.  The actress long struggled with psychiatric and emotional problems, along with drug and alcohol abuse, but she was convinced John would leave Jackie for her.

Marilyn's friend Jeanne Carmen reportedly confirmed the starlet's beliefs.

"Can't you just see me...as first lady," Marilyn asked Carmen.

According to the Daily Mail, Andersen wrote JFK's Air Force aide, General Godfrey McHugh, revealed Jackie knew about John's affairs with other women.  Jackie knew details about the girls including the women's personal accomplishments.

The affairs angered Jackie, but a close friend of JFK, George Smathers, told the author of the "she was willing to look the other way as long as he was careful and didn't humiliate her."

Jackie allegedly feared her inability to sexually satisfy JFK was going to force him into the arms of another woman, according to the Daily Mail.  "But she complained of the President's love-making to her long-time confidant Dr. Frank Finnerty, claiming 'he just goes too fast and falls asleep.'"