Prince Charles told Princess Diana he didn't love her the night before the couple tied the knot, according to the Princess of Wales' former astrologer.
Speaking on new ITV documentary The Diana Interview: Revenge of a Princess, Penny Thornton said Charles' bombshell confession wanted to make Diana call the whole wedding off.
Thornton, who started consulting Diana in 1986, said it was one of the most unbelievable things Diana had ever talked about.
"One of the most shocking things that Diana told me was that the night before the wedding, Charles told her that he didn't love her.
"And that was a truly terrible thing to do to your future bride that you're going to marry in St Paul's the very next day.
"I think Charles didn't want to go into the wedding on a false premise, he wanted to square it with her."
Thornton said Charles' revelation left Diana devastated and almost saw her put an end to the wedding.
She explained Diana was thinking of not showing up.
"She didn't want to go through with the wedding at that point, she thought about not attending the wedding," she added.
In the documentary, others took aim at Charles, with royal photographer Ken Lennox calling the Prince "atrocious" for leaving Diana minutes after she gave birth to Prince Harry so he could go and play polo.
Lennox was waiting outside the hospital to take photos of the couple and their newborn son.
He thought the rumour was so ridiculous he bet £50 it wasn't true. He lost.
"I lost £50 because I couldn't believe that a man with a newborn baby was going to leg it and play some daft game of polo.
"Doing something like that to a wife with a newborn baby was atrocious.
"If he thought he could treat his wife like that, he was in deep trouble."