Prince Charles and Princess Diana reportedly tried so hard to hide the truth from the public that their marriage was falling apart. Queen Elizabeth, on the other hand, reportedly felt miserable and drained during the royal couple's separation.

Before the Prince and Princess of Wales divorced, Her Majesty reportedly made herself available to Princess Diana. Reports say that whenever there's a gathering, the Princess usually expressed her feelings about her relationship with Prince Charles. Eventually, Queen Elizabeth started to dread with the idea of meeting her daughter-in-law.

According to the book The Queen & Di: The Untold Story, Ingrid Seward claims Her Majesty grew tired of meeting with Princess Diana due to her constant complaints. The monarch reportedly left feeling confused, drained, and despondent - which was an uncommon state for a woman who's accustomed to her position's certainties.

Seward added Queen Elizabeth cut down the number of times she would meet the Princess of Wales due to the stressful meetings. Ever since they got married, Princess Diana reportedly suspected Prince Charles having an affair with Camilla Parker Bowles. But while a lot of people were aware of the Prince Of Wales feelings for the latter, Her Majesty reportedly resented her back then.

Based on the Amazon Prime documentary Diana: The Woman Inside, the Princess of Wales' bodyguard Ken Wharfe claimed Camilla never gave Prince Charles the chance to fix his marriage with his wife. Because of this, the monarch reportedly felt unhappy with her as she became one of the main reasons why the former royal couple separated.

Wharfe said Her Majesty could not forgive Camilla as she didn't give Prince Charles and Princess Diana the chance to save their failing marriage. He added that Queen Elizabeth wouldn't condone her son's adultery and wouldn't forgive Camilla for not leaving the Prince of Wales alone to at least let his marriage to recover.

Princess Diana was reportedly desperate to make things work with her husband, and she even argued with Camilla. In the secretly-recoded tapes for Andres Morton's book, the Princess of Wales reportedly confronted Camilla regarding her affair with Prince Charles, and she told her that she already knew what's going on between the two of them.

The Princess of Wales hoped she could save their marriage for the sake of their children, Prince William, and Prince Harry. But in 1996, Prince Charles and Princess Diana finalized their divorce, and he married Camilla in 2006. And now, Queen Elizabeth seemed to be on better terms with the Duchess of Cornwall.