It’s been 20 years since Princess Diana‘s death, yet her ex-husband, Prince Charles, and his second wife, Camila Parker-Bowles, still can’t shake the late Princess’ memory. It’s a widely known fact that the Prince wasn’t faithful to Princess Diana during their marriage. Instead, he had an affair with a woman from his past, Camilla. But what many don’t know is that Princess Diana knew about their relationship (which began even before they tied the knot) — and she wasn’t silent about it either.

MORE: Princess Diana and Prince Charles’ Royal Marriage Was Never Likely to Succeed — See a Timeline of Their Relationship Breakdown

Now, the host of two documentaries, including Diana: In Her Own Words, is revealing how the princess really felt about her husband’s betrayal. “I remember crying my heart out on my honeymoon,” she said, likening herself to a “sacrificial lamb.”

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We hate the thought that Princess Diana was that miserable in her marriage when it had only started. But, apparently, she didn’t let that misery stop her from confronting Prince Charles and Camilla about their affair. The Princess recounted fights she had with her husband about his girlfriend and what it was doing to their marriage. And, she even took it upon herself to speak to Camilla face-to-face.

MORE: Princess Diana Was Scared She’d Lose Her Boys to the Royal “Establishment” If She Spoke About Her Split From Prince Charles

“I said, ‘Camilla, I’d just like you to know that I know exactly what’s going on.’ And she said, ‘I don’t know what you’re talking about,’” she recalled. “I said, ‘I know what’s going on between you and Charles… Don’t treat me like an idiot.’”

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