As a busy royal, Kate Middleton and her husband Prince Charles are required to have royal engagements in the United Kingdom and several parts of the world. Countless royal fans have watched their royal tours, and among them was Prince Harry's girlfriend, who had a big realization while tuning in; what happened?

Royal expert Katie Nicholl opened up about the Duke of Sussex's past relationship in her 2017 book "Harry: Life, Loss and Love."

The Prince was previously linked to Cressida Bonas, a popular figure known for her dancing and acting skills.

According to Express UK, Bonas' ancestors have direct links to King Edward VII. The actress is the granddaughter of Edward Curzon, 6th Earl Howe.

Nicholl revealed in her book that Bonas watched TV coverage of the Duke and Duchess of Cambridge while they were on a royal tour in New Zealand and Australia in 2012.

While sitting at home, the actress witnessed how the royal couple interacted with people, and she was left "completely spooked" by it. The royal expert described it as a "wake-up call" for her.

Bonas reportedly didn't want "that sort of attention," and she told Prince Harry about it.

However, the Duke was adamant about her decision, and he didn't want to end their relationship.

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Harry was "in love" with the actress, and he did his best to convince her to stay and make their connection work, but "Cressida's mind was made up."

After breaking up in 2014, Prince Harry reportedly suffered "a real blow," and Nicholl believes Bonas broke his heart.

Despite ending their connection, the two remained good friends.

"Twice [Harry] had been left heartbroken because the women he had fallen in love with didn't want to share the life he had been born into," Nicholl added.

Not the First Time Prince Harry's Heart was Broken Because of his Royal Status

In the book "Battle of Brothers," written by royal biographer Robert Lacey, Prince Harry's ex-girlfriend, Chelsy Davy, broke things off shortly after the wedding of Kate Middleton and Prince William.

Davy reportedly told the royal that she couldn't make the same sacrifices as the Duchess of Sussex did for the firm, like "molding" her life around the public eye.

Harry's ex is said to have struggled with public attention, and the royal wedding was her last straw, making her realize that marrying into the royal family isn't the life she wanted.

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