Hollywood's Nastiest Feud EVER! Jackie O. Died Hating Liz Taylor — Here's Why

Glamorous Jackie Kennedy Onassis hated Elizabeth Taylor because she was certain the notorious man-eater had seduced her husband, the late president John F. Kennedy!

Newly revealed diaries kept by Liz show the depths of the feud between Jackie — who died at 64 in 1994 — and Liz — who passed in 2011 at the age of 79.

Liz's eye-opening confessions show that while handsome JFK was campaigning for the White House in 1960, the "Cleopatra" star had several private meetings with "Jack" at a secluded bungalow in Beverly Hills, Calif.

A source says Liz, who was married to fourth husband Eddie Fisher at the time, was "thrilled to be invited to meet Kennedy" during one of his California fund-raising visits.

The insider reveals the two "hit it off so well, he invited her to see him a number of times."

But when word of the dangerous liaisons got back to Jackie, she exploded in a jealous rage that forced Jack to keep Liz at a safe distance.

"Had it not been for Jackie's jealousy, Taylor would undoubtedly have been part of what became known as Camelot, his inner circle," spilled the source.

Although Liz swore to friends "her relationship with Kennedy never went beyond friendship," Jackie was convinced her philandering hubby had bedded the Hollywood star "and said some vicious things that got back to Liz," claims the source.

"Jackie was so paranoid her husband was cheating, which he did so often, she was never able to trust any woman who showed any interest in her husband."

But Jackie had a good reason to worry!

One source says that way back in 1948, Liz and JFK DID have a dirty dalliance — one that included Robert Stack!

JFK, then a newly elected congressman, was invited to Robert's home, where he found beautiful 16-year-old Liz waiting.

After "some chitchat and lunch," Kennedy suggested they all go for a swim — "and everybody got into the pool for Liz's first three-way," according to the source.

JFK went on to marry Jackie in 1953 — and racked up a string of impressive female conquests in the years that followed, enraging his prim and proper wife.

Among the women he bedded were the then-60-year-old movie legend Marlene Dietrich, young White House intern Mimi Alford, Mafia moll Judith Campbell Exner, Jackie's press secretary Pamela Turnure — and, most famously, sultry bombshell Marilyn Monroe, who brazenly flaunted their affair in front of the world!

"Jackie's fury was fueled by 'tarts' like Marilyn Monroe who always flocked around Kennedy and made her life a living, walking embarrassment because he was tempted so often by so many women," the source notes.

"It made her a woman who was frenzied and paranoid."

As for Liz, a source says one of her diary entries sadly laments she "could never convince Jackie that she did not have an illicit relationship with her husband."

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