A special documentary on Princess Diana reveals that she knew in her "heart of hearts" that there would be an element of "tragedy" in her life before she married Prince Charles.

A former close friend told the PBS special documentary "In Their Own Words: Diana, Princess of Wales" that Princess Diana had a "rude awakening" after her marriage to Prince Charles. Meanwhile, a royal photographer close to Princess Diana claims she informed him after their marriage ended that she still loved Prince Charles.

A friend claims Diana knew the magnitude of marrying Prince Charles

Kent Gavin worked as a royal photographer for the Daily Mirror for over 20 years, and he formed a strong friendship with Princess Diana while photographing her. Besides, Debbie Frank, a close friend of Princess Diana and a professional astrologer, claimed she walked into this job and she recognized the magnitude of it; but the astrologer thinks Diana felt in her heart of hearts that there was a tragedy with it.

On July 29, 1981, Princess Diana married Prince Charles in a highly publicized wedding at St. Paul's Cathedral. While Princess Diana and Prince Charles had an aristocratic upbringing, the pair was 12 years apart in age and had only spent time together 13 times before being engaged.

Princess Diana was just 20 years old at the time of their wedding, as per Express.co. Their wedding was dubbed "the wedding of the century" and was witnessed by an estimated 750 million people worldwide.

Prince William and Prince Harry were born to the royal couple in 1982 and 1984, respectively. However, their marriage began to show gaps from the start, with Princess Diana later claiming the marriage had "gone down the drain" after the birth of their second son. Princess Diana struggled to adjust to royal life and had mental health issues.

Prince Charles eventually reconciled with Camilla Parker-Bowles, a former girlfriend whom he had dated in the 1970s. The Princess of Wales pursued her interests, including a relationship with riding instructor James Hewitt.

Due to the nature of their seemingly miserable marriage, the Prince and Princess of Wales had been a frequent subject of tabloid gossip by the late 1980s. Prime Minister John Major announced their split in the House of Commons in 1992, shortly after Andrew Morton's biography "Diana: Her True Story" was released.

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Prince Charles, Princess Diana's marriage was doomed from the start

After Princess Diana's controversial appearance with BBC Panorama in 1995, in which she once again revealed her struggles as a member of the Royal Family, tensions between the royal couple rose. Following the broadcast of the interview, the Queen wrote to Charles and Diana, requesting that they start divorce procedures.

Princess Diana died in a car accident two years later, at the age of 36, in 1997. The paparazzi had been persistent in their pursuit of her and her lover, Dodi Fayed. Her untimely death caused worldwide grief, with an estimated 2.5 billion people tuning in to witness her televised burial.

Per Business Insider, Princess Diana's travel to Pakistan in 1997 would have been the most plausible, given she and Prince Charles divorced in August 1996. As previously revealed by Insider's Mikhaila Friel, details of Prince Charles' romance with Camilla Parker-Bowles, now the Duchess of Cornwall, were leaked to the press in 1992, following which he and Princess Diana made public appearances separately.

Despite her statements to Gavin towards the end of her marriage, Diana was unhappy at the time of her wedding, according to the royal photographer. He was with Charles and Diana at Smith's Lawn the day before the wedding, and he claimed: "she was quite upset and left." Princess Diana later admitted that she had reservations about marrying the prince throughout their engagement.

From the beginning, Princess Diana and Prince Charles had a rocky relationship. Debby Frank claims the Prince and Princess of Wales had personalities that were completely contradictory, resulting in compatibility difficulties.

Princess Diana was "going through a terrible moment in her marriage because her husband was having an affair with Camilla and nobody knew about it," she claimed. Frank added that Princess Diana felt desperate. She went on to say that the two "were very different" as while Charles and Diana were both Cancers, it was their moon signs that made things complicated for them, The News reported.

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