More than 25 years after John F. Kennedy Jr. and Carolyn Bessette-Kennedy died in a 1999 plane crash, new reporting uncovers the fiery volatility within their marriage, with long-held tension, alleged infidelity, and deep personal hardships beneath the romantic glow of this celebrity couple.

Details resurfaced this week following reporting by RadarOnline, which outlined private accounts from friends, authors and individuals who interacted closely with the couple in the years leading up to their deaths.

Carolyn expressed a fixation on Kennedy early in her life, according to author Steven M. Gillon. The source explained, "That obsession was not the only disturbing revelation about Carolyn."

Gillon also wrote that, when asked about her ambitions, "I want to be famous. Maybe if I hook up with the right guy, I will be famous," according to the recollection.

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Accusations of infidelity fueled the conflict significantly. A description from insiders cited in RadarOnline had it that Kennedy thought Carolyn had reconnected with former Calvin Klein model Michael Bergin.

According to Edward Klein's book "The Kennedy Curse: Why Tragedy Has Haunted America's First Family for 150 Years," a friend of Bergin remembered one clandestine encounter thus: "Michael asked me to leave immediately, and when I went out, I found Carolyn Bessette-Kennedy hiding under the staircase."

Klein further claimed that JFK Jr. had difficulty accepting the circumstances. In his written work, Klein recorded that Kennedy was baffled and thought, "In his narcissistic self-absorption, he found it inconceivable that a woman would choose another man over him."

Per Yahoo! Entertainment, the marriage reportedly deteriorated further as concerns mounted regarding Carolyn's alleged drug use. Sources said that Kennedy shared these concerns with his sister Caroline shortly before his death.

By 1999, it seemed as though the relationship had reached a breaking point. As RadarOnline explained, "JFK Jr. moved out of their apartment and checked into a $2,000-per night room at the Stanhope hotel."

He stayed at that hotel until July 16, 1999, when he, Carolyn, and her sister Lauren left for Martha's Vineyard to attend a family wedding. Shortly after takeoff, their plane crashed, killing all three.

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