Princess Diana said she developed bulimia after discovering Prince Charles' affair with Camilla Parker Bowles

Footage broadcast for the first time by Channel 4 was recorded in mid-1990s when ‘War of the Waleses’ was at its peak

'He was all over me like a rash' (Reuters)

Princess Diana developed bulimia from the stress of being pregnant with her first son at the time she discovered her husband was having an affair, according to a new Channel 4 documentary.

She said at the start of their relationship Prince Charles “was all over [her] like a rash”.

“He would ring me up every day and then not contact me for weeks; he wasn't very consistent in his courtship,” she said.

Channel 4’s controversial documentary Diana: In Her Own Words included footage filmed between the end of 1992 and mid-1993, when the so-called ‘War of the Waleses’ was at its peak.

During the frank recordings, Princess Diana revealed she had only met Charles 13 times before their wedding day but on their second meeting he chatted her up “like a bad rash”.

"I was brought up in a way that when you got engaged to someone, you loved them," she said.

In conversations with her voice coach Peter Settelen, she also said that after their marriage Prince Charles only wanted to make love once every three weeks.

Describing her feelings when Prince Charles said they were in love “whatever love means” in a television interview about their engagement, she said this ”threw me completely, it traumatised me".

She spoke of her difficult pregnancy with Prince William in the 1980s and knowing that her husband was having an affair with Camilla Parker Bowles.

She reportedly asked the now Duchess of Cornwall to leave her husband alone, according to her ballet teacher, Anne Allan.

When that did not work, Princess Diana went to the Queen for advice.

“I went to the top lady, and I was sobbing, and I said what do I do?" Princess Diana said. "And she [the Queen] said, 'I don't know what you should do, Charles is hopeless', and that was it."

Princess Diana developed bulimia around this time.

"Everyone in the family knew about the bulimia, and everyone blamed the bulimia for the failure of the marriage," she said, adding that the eating disorder was the most "discreet" way to harm herself rather than alcohol or anorexia.

In 1985 when she was the mother of two young princes, she fell in love with Barry Mannakee, a Royal Protection Officer. She said she was "happy to give all this up" and leave the Royal Family to be in a relationship with him.

"I never should have played with fire," she said.

Shortly after he left his job as her bodyguard, Mr Manakee was killed in a motorbike accident in 1987.

She added: "He was the greatest lover I ever had."