"She went out with a boy called Paolo Liuzzo, an American guy," she said.
"They didn’t go out for long, less than a year," she continued, before revealing a shocking truth behind their split.
"The end of the relationship came when it was discovered that he was charged with assault and battery in the case of a death of a student at university.
"So they broke up when his criminal record was revealed."
In an interview withthe Mail in 2007, Paolo said that by the end of 2005 their affair was being taken so seriously by Princess Beatrice that she spoke longingly of introducing him to Queen Elizabeth II and subsequently the whole royal family.
"She said, 'I'd love you to meet Granny'," Liuzzo recalled at the time. "But she said Chelsy wasn't allowed to meet her and usually you don't get introduced to her until you are engaged.
"Bea wanted to fly to New York to visit my mother but, I'll be honest, I've never brought a woman back to my house to meet my family unless it was someone I would be proposing to.
"We'd started joking about getting married and having kids.
"I wasn't sure I wanted to get in that deep with Bea. I loved her but I wasn't in love with her.
It appeared Princess Beatrice had dodged a serious bullet with Liuzzo, who was later charged with cocaine possession.
WATCH: Princess Beatrice and Edoardo Mapelli Mozzi look SO loved up
Following her relationship with Liuzzo, the Duchess of York entered a ten-year relationship with Uber executive Dave Clark.
Mollard believes that the relationship may have been a passionless one, saying that "it was probably one of those relationships where they were comfortable, they really liked each other, but there just wasn’t that spark."
According to the royal commentator, Dave went on to marry another woman named Lynn Anderson in Italy less than two years after their separation.
Furthermore,Expressreported that Prince William had initially introduced his cousin Beatrice to Dave at the birthday party of Pierce Brosnan’s son Sean in 2006.
However, a source told the Daily Mail in 2015 that “William isn’t a huge fan of Dave," and that the Duke might've contributed to their split.
"It’s fair to say that if Beatrice had asked the Queen for permission to marry Dave, and she in turn asked William privately for his view, she may not have been given a glowing report," the source added.
Princess Beatrice was in a ten-year relationship with Uber executive Dave Clark.
"Since then she’s had a short-term relationship with Wilfred Frost, the son of David Frost," Mollard said, adding that Princess Beatrice may have a penchant for playboys.
Princess Beatrice's current partner is 34-year-old Italian property developer Edoardo Mapelli Mozzi - who specialising in discreetly finding and developing expensive homes for rich clients.
He's also the step-son of the late Christopher Shale, and it is thought that he had connections as a friend of the royal family prior to his romance with Princess Beatrice.
However, Mollard also discussed the rumours that Beatrice may not be given the same honour that Eugenie was given for her wedding, due to her future fiance having a two-year-old son with another woman.
She said: "It’s interesting, there has been some talk that she can’t have the sort of wedding that her younger sister Princess Eugenie had.
"I suspect because of the fact that he [Edoardo] had a child with somebody else and didn’t marry her."