Elizabeth Edwards is threatening to divorce her husband, John, after learning of allegations he had committed adultery with more than one woman, the National Enquirer is reporting.

According to the Enquirer, the allegations are in a book proposal by former Edwards aide Andrew Young in which he says he falsely claimed to have fathered Rielle Hunter's 19-month-old daughter, Frances.

Edwards had an affair with Hunter during the 2008 presidential campaign. According to The New York Times and other reports quoting sources, Edwards is considering declaring he's the little girl's father, which he has previously denied.

"Elizabeth was read portions of Young's book proposal, and she flipped out," a source told the Enquirer. "What really pushed her over the edge is Young's allegation that John had other affairs with women on the campaign trail. Elizabeth basically told John that if she found out that was true, she'd have to divorce him because then he'd be a 'serial cheater.'"

The Enquirer has another source that says John Edwards is denying the allegations, telling his wife, "Young's book is a pack of lies."

The paper reports that Elizabeth Edwards' divorce threats include taking half of their joint $53 million worth and going public with political secrets in open divorce court.

"Elizabeth knows every dirty little secret in her husband's political past. She's been his confidant for years, and she's always kept quiet. But now she's prepared to reveal all his secrets in open court," a source told the Enquirer.

Elizabeth Edwards has stage four metastatic cancer, which her husband said was in remission when he had an affair with Hunter.

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