Everybody in Prince Charles' circle of friends said Princess Diana was an ideal match for the heir to the throne long before they started seeing each other. 

Everybody, even the woman he left Princess Diana for, Camilla Parker Bowles. 

When he presented Lady Diana Spencer as a potential suitor, Camilla was rooting that he picks her, as per biographer Howard Hodgson. 

In 2007, he wrote, "Charles: The Man Who Will Be King," explaining how the Duchess of Cornwall attempted to welcome Diana after it was announced that she would become the Princess of Wales. 

After the announcement of their engagement, Camilla even reportedly wrote to her, "Let's have lunch soon when the Prince of Wales goes to Australia and New Zealand. I'd love to see the ring. Lots of love, Camilla." 

According to the author, Camilla's letter was "genuinely friendly" and that her intentions were "good." 

The two had a great lunch together. 

However, years later, Diana later remembered the meeting less fondly, believing that Camilla was only using it to work out when she would able to see Prince Charles after the wedding. 

She told her biographer, Andrew Morton, "I didn't know about jealousy or depression or anything like that. I thought as far as she was concerned, that was her communication route. Still too immature to understand all the messages coming my way."

Camilla and Diana formed a close bond and had gotten to know each other. 

They used to hang out at Bolehyde Manor, where Camilla lived with her husband at the time, Andrew Parker Bowles. 

Diana, who used to be a nanny, would help Camilla look after her to small children, Tom and Laura. 

"Camilla wanted to support her because she thought she was fun and made the Prince happy."

However, after the engagement, Lady Diana Spencer became distrustful of her friend. 

According to Andrew Morton's book, he described how Diana was so upset by the Prince of Wales' decision to give Camilla a bracelet, with the initials G and F engraved in it just before his wedding in July 1981. 

Diana was convinced that the initials meant "Gladys and Fred," which was said to be Prince Charles and Camilla's pet names for each other. 

She also told Morton how she surprised Prince Charles and his friends by attending a celebration for Camilla's sister and engaged in a conversation with Camilla, where she told her she knew about their affair. 

Princess Diana later recalled that Camilla said she had beautiful children before asking her what more could a princess still want in life.

And the Princess of Wales' response to that was, "I want my husband." Both women were left visibly shaken by the encounter. 

When she confronted Prince Charles about the affair, the heir to the throne reportedly told her, "I refuse to be the only Prince of Wales who never had a mistress."

A couple of years pass by, there was no more contact between Camilla and Diana, but their relationship became very public when the royal marriage started shattering. 

In an interview with Martin Bashir, Princess Diana famously said, "There were three of us in this marriage, so it was a bit crowded." 

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