Aug. 13, 2009 -- While Bernard Madoff swindled tens of millions of dollars from one of the country's leading Jewish charities, Hadassah, he was also having an affair with its chief financial officer, Sheryl Weinstein.

Weinstein reportedly admits the affair in a book to be published later this month, "Madoff's Other Secret: Love, Money, Bernie and Me," to be published by St. Martin's Press on August 24. The book's subject was first reported by Bloomberg News.

Weinstein had denied a romantic relationship with Madoff to ABC News earlier in the summer. She is scheduled to appear on Good Morning America for her first exclusive television interview Aug. 25.

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And she did not acknowledge the affair with Madoff when she testified against him at his sentencing hearing on June 29 and called him a "beast."

She told Judge Denny Chin she had met Madoff 21 years ago at a business meeting when she was the chief financial officer of the Jewish women's charity.

"I now view that day as perhaps the unluckiest day of my life," she said as she described how her investments with Madoff cost her family its savings and the family home.

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Weinstein did not return calls seeking comment today and it is not known how long her affair with Madoff lasted or whether or when she told her husband of 37 years about the extra-marital relationship.

She told the judge, with her husband seated beside her, that Madoff "should not be given the opportunity to walk into our society again."

Madoff had his back to her as she spoke in court and did not turn around to look at her.

"If she wants to announce to the world that she had an affair, that's her business," said Madoff's lawyer Ira Sorkin. "I have no comment on the truth or falsity of what she says but I hope she takes some pleasure from telling everyone that she cheated on her husband."

Madoff's long-time secretary, Eleanor Squillari, recalled that Weinstein would often call Madoff and that "he would roll his eyes and then they would go and meet at a hotel."

Asked about Squillari's account in July, Weinstein said she had no recollection of any such meeting. "I have no idea why she would say that," Weinstein said.

Hadassah Charity

According to Hadassah, the charity had invested more than $40 million with Madoff as of 1997, when it stopped adding principal. It believed its account was valued at $90 million when Madoff was arrested.

A spokesperson had no immediate comment on the affair involving its former chief financial officer and Madoff or on the role of Weinstein in placing the charity's money with Madoff.

Asa Eslocker contributed to this report.

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