Prince Charles knew that when he popped the question, there was no margin for error.
In The Story of Diana, a two-night television event from PEOPLE and ABC, insiders open up about Charles and and Princess Diana‘s romance, which at one point seemed like a fairy tale — but eventually was revealed to have deep cracks in its foundation.
Even when the couple married, those who knew Charles well — including his former girlfriend Jane Ward — worried that Diana, just 19 when she got engaged, was too young to tackle the often-intrusive life of a royal.
“I watched it on the television, and I remember looking across at everyone sitting there,” says Ward. “I just said, ‘Sadly, I just don’t think this will survive. I think she’s just too young to take it all.’ ”
Charles himself was acutely aware of the pressures he faced in finding a bride — and that he wouldn’t have the opportunity to ease into the relationship the way most courting couples would. While on an official visit to India, he told the press, “I’ve got to get it right the first time, or you’ll be the first to criticize me.”
Charles and Diana only saw each other a dozen times before they got engaged in 1981. When they did announce their engagement, Charles famously responded to the question of whether he was in love with his bride-to-be by saying “whatever ‘in love’ means.”
Royal biographer Sarah Bradford says that Diana was in love with Charles — and that Charles at least claimed to be.
“Diana was certainly in love with Charles, and I think at times, he was in love with her,” she says in The Story of Diana. “Or he said he was.”
Of course, now we know who Charles was in love with: Camilla Parker-Bowles, now Camilla, Duchess of Cornwall, his wife.
“A lot of us had known already that Prince Charles was in love with somebody else, and had been, sort of almost all his life,” says fashion journalist Meredith Etherington-Smith.
Charles’s cousin, India Hicks, who was a bridesmaid in Charles and Diana’s wedding, says that in the end, Camilla is Charles’s perfect match.
“He really found a soulmate,” she says. “They share a lot in common, their passions are more similar and aligned.”
For full PEOPLE coverage of the 20th anniversary of Princess Diana’s death:
•The Story of Diana, a two-part television event from PEOPLE and ABC, airs on ABC Aug. 9 and 10 at 9 p.m. E.T.
•PEOPLE’s special edition Diana: Her Life and Legacy is available now
•Princess Diana: Behind the Headlines is streaming on the new People/Entertainment Weekly Network (PEN). Go to PEOPLE.com/PEN, or download the PEN app on your favorite mobile or connected TV device