The 70-year-old is releasing a new tell-all book about the Duchess of Sussex and her husband Prince Harry, Meghan and Harry: The Real Story, based on interviews with her Royal sources.
Appearing on FUBAR Radio to discuss her book, Lady C accused Markle of orchestrating both the couple's move to Los Angeles and their decision to step down as senior members of the Royal Family.
"I have no doubt that they tell themselves they're doing the right thing, but we also need to remember that history is littered with people who thought they were doing good," she said.
"I only have to mention Adolf Hitler, not that I'm putting them in the same camp as him. It doesn't alter the fact that Adolf Hitler thought he was doing good for the world. Mao Zedong, who also killed hundreds of millions of his own people, he thought he was doing good.
"So I'm sorry you know, history's littered with people who are deluded enough to think that because they want black to be white, that black is white. Black is black and white is white.
"If you believe for one second that Harry had anything like this up his sleeve you believe in the tooth fairy and the pig airline. They don't exist. Absolutely not.
"Had Harry married anyone else, the Duke and Duchess of Sussex would be here safe and sound in Kensington Palace. It's completely Meghan."
Lady C went on to claim that Princess Diana would have been "completely horrified" by her son's decision to leave the UK were she still alive. body check tags ::