Breaking up with his wife Je Lan after a turbulent time as National leader was the worst mistake of his life, Don Brash says.
In his autobiography, Brash talks about the end of his first and second marriages to Erica and Je Lan and likens himself to famous men who have taken risks for a sexual relationship.
He blames in part his workaholism but also the strong male biological urge. "The result of that drive is that many men take huge risks for the chance to have a sexual relationship. Among American presidents the names of John Kennedy and Bill Clinton immediately spring to mind, while in earlier years Franklin D. Roosevelt, Wendell Wilkie and Warren Harding would have come to mind.
"Prominent Christian leaders, such as Martin Luther King, Paul Tillich and of course several televangelists, are also known to have had extra-marital affairs."
Brash's leadership of the National Party was an extraordinarily turbulent period in his life, including his infamous Orewa speech on race relations, which saw his personal popularity soar.
But he stood down after allegations swirled about an affair with businesswoman Diane Foreman and in the wake of Nicky Hager's book The Hollow Men, which detailed hundreds of private emails which were either leaked or stolen from him during his time as leader.
A police investigation never found how the emails ended up with Hager.
Brash's book skirts around suggestions of his affair and he does not refer to Foreman, though he refers to women in his life who had been supportive both during and after his marriage to Je Lan, which ended in 2007, the year he left Parliament.
Speaking ahead of the book's release, Brash said he did not want to cause people further pain by talking about the alleged affair.
But once he decided to embark on an autobiography, an honest assessment of his life had to acknowledge "there were some pretty miserable failures and my personal life was obviously one".
"I felt I couldn't gloss over it, I had to discuss it. At the same time I didn't want to reopen too many old wounds in a way that would be painful to both Je Lan and Erica, on the one hand, and other people involved, potentially, in the other."
- The Dominion Post
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