By Mick Krever, CNN

“I was a full-on racist by the time I started working for him.”

That is the shocking revelation from Nelson Mandela’s long-time personal assistant, gatekeeper, and trusted aide, Zelda la Grange, a white Afrikaner.

“Now looking back, if you [asked] me at the age of twenty-three I would probably have denied being a racist,” she told CNN’s Christiane Amanpour on Tuesday. “Now it's easier, because you can recognize the change in yourself.”

La Grange was born the year after Mandela was sent to prison; little in her upbringing suggests she was destined to be confidant to the world’s foremost black liberation leader.

She had been so ignorant of her country’s politics that she hadn’t even heard of Mandela when it was announced he would be released from prison, in 1990.

“I was swimming in the pool on that day in February,” she told Amanpour. “And [her father] came outside and he said to me, ‘We are in trouble.’”

“And I said, ‘What are you talking about?’”

“And he said, ‘The terrorist is being released.’”

“I said, ‘Who is that?’”

“And he said, ‘Nelson Mandela.’”

“I continued swimming. It didn't affect my life. I didn't know who he was. My father apparently knew who he was.”

When Mandela assumed the presidency after that landmark election in 1994, la Grange happened to be applying for a menial typist job in the office of the presidency when Mandela’s then-secretary came into the room and said she needed someone “right now.”

It was all, she said, “so unlikely to happen.”

Her first meeting with Mandela was “the turning point in my life,” she told Amanpour.

“He was kind. He smiled. He extended his hand, and he spoke to me in my own language. He spoke to me in Afrikaans. And that is the last thing you expect of him, because I was brought up to fear this man.”

“And that just destroyed my defenses immediately, and I broke down and I was crying, and he said to me, ‘No, no, no, you're overreacting.’”

“And if a president tells you you’re overreacting, you pull yourself together very quickly.”

It would be the beginning of a lifelong friendship and alliance.

Bringing excitement to Mandela’s life

In those first years of Mandela’s presidency, La Grange said, “there was no excitement really, I think, in his life other than politics.”

“At that stage, I mean, I didn't really think of the president entering into a romantic relationship.”

That all changed during a state visit to Paris.

“I got to his room and his door was closed. You know, of course the president's got a lounge and a dining room and a room and so and so – this door leading to his suite was closed.”

She ran the president’s spokesman and said, “There’s a problem – the president's door is closed and there's a lady inside.”

“I just knew, we all knew, if it's one thing not supposed to happen it's that the president's door is closed when he’s alone with a woman.”

There was broad concern at the time, she explained, that the president’s opponents could “put him in a compromising position” – in other words, frame him.

“I got called to the president's suite and he said to me after a while, ‘This is my friend Graça Machel, and I want you to look after her and she's going with us to the next event, so please keep an eye on her.’”

“And that was the start of this wonderful, romantic relationship between the two of them and them. And yeah, it turned out to be the best thing that could ever happen to him.”

“She brought him about to understand or to appreciate the different things in life again – beautiful music, look at the flowers, walking hand in hand in the street early in the morning or late in the afternoon. Ordinary things that we take for granted.”

Nelson and Elizabeth

Mandela may very well have been the only person who could call Queen Elizabeth, “Elizabeth.”

“It was fascinating to watch, and Ms. Machel at one point said to Madiba, ‘You can't call her Elizabeth!’”

“And then Madiba responded and he said, ‘Well, she calls me Nelson.’ So it was very entertaining to watch.”

“He respected the Queen but it was a warm friendship and I think they recognized each other as human beings – each other's humanity. And I think the Queen enjoyed that really.”

It was probably rare for her, Amanpour said.

“I think very rare for her.”

“He walked up to her when we visited Buckingham Palace at one occasion, and he said to her, ‘Oh, Elizabeth, you've lost weight.’”

“Not something that everyone gets to tell the Queen of England.”

“She laughed. You know, she was entertained probably by this directness. And with no shame and no ill intent – you know, was Madiba loved charming women and he was always very complimentary of women. So it was part of who he was.”

Entertaining the Iranians

So close were la Grange and Mandela that he insisted she attend all state dinners – even those private meals with just the president and his counterpart.

Even, she explained to Amanpour, a private dinner with Iranian President Mohammad Khatami.

“It was the weirdest experience, because suddenly I find myself with only these two people, Nelson Mandela and President Khatami, and I have to give President Khatami the history of South Africa.”

“And Madiba was happily eating. He's not conversing. He's just, you know, looking at the two of us, sharing history.”

Perhaps an opportunity, Amanpour asked, for Mandela to simply enjoy his meal?

“That was I think exactly it. For once he could really just enjoy his food and he was just watching me entertaining the president.”