Prince Charles and Princess Diana's marriage was surrounded by a lot of rumors about the Prince of Wales' infidelity. As their so-called fairytale love story ended with a divorce, it changed the late People's Princess' life, while her estranged husband received a warning before he admitted he was unfaithful to his former wife.

In a bombshell interview, the Duke of Cornwall admitted he was unfaithful to the mother of his children, Prince William and Prince Harry. While talking to Jonathan Dimbleby, he revealed some aspects of his life, explaining that it wasn't long before Camilla Parker Bowles came into the picture.

So, when did his rekindled romance with the Duchess of Cornwall begin at the time? It was when his marriage started to break down.

Former press secretary Dickie Arbiter warned Prince Charles of the implications he might experience before he did the interview. On the Channel 5 documentary Charles and Camilla: King and Queen in Waiting, he said he warned the future king his revelations should be truthful.

"You cannot deny anything; you cannot leave anything out. And nothing was left out," Arbiter said, via Mirror Online. With the huge controversy he was in, millions of people watched the ITV interview, but, sadly, it shocked the royal family.

Prince Charles, at the time, promised that he was faithful to Princess Diana after their marriage, but not until it "irretrievably broke down." Arbiter added that Charles was distraught with the negative news about him. It was so adverse that it already became vicious.

This even didn't just change Prince Charles' life but Princess Diana's, too. In the 2007 issue of The Observer, writer Oliver Marre discussed how the pressures of royal life changed the Princess of Wales radically, Express noted.

Prince Charles' ex-deputy private secretary Sarah Goodall revealed that a courtier once warned Princess Diana that she would become a "complete and utter b****" after her engagement. Goodall explained that being part of the royal family too early and being under the "massive expectations" came with "serious consequences" for any newcomers.

Fortunately, Princess Diana managed to champion a lot of causes, leaving a legacy of compassion. Her efforts to remove the stigma that still surrounds HIV/AIDS until today made a significant impact during the 1980s. When she shook the hand of AIDS patients, she tried to shut down the beliefs that the disease could be transmitted through skin-to-skin contact.