The mistress of disgraced vice presidential candidate John Edwards has come forward with a public apology for "wrong, selfish behavior" that stemmed from falling in love with the married politician, having a child with him and then writing about it.

Rielle Hunter wrote her public apology on the Huffington Post, ahead of the release of a revised edition of her book, "What Really Happened: John Edwards, Our Daughter and Me."

The affair played out while Edwards was the Democrats' vice presidential candidate and his wife Elizabeth was dying of breast cancer.

"I behaved badly. That may seem obvious to you but it's taken me a long time to admit that, even to myself," she wrote. " I hurt Elizabeth and her kids. I hurt her family. I hurt John's family."

"Unfortunately, I was not thinking about anyone but myself. I was selfish. I fell in love with John Edwards and wanted to be with him and that desire trumped everything else," she said.

Phil Ellsworth/ABC

Edwards and Hunter started their affair in 2006 when Edwards had been married to his wife Elizabeth for 29 years. The Edwards had four children together.

After news reports began reporting on the affair in 2007 and 2008, Edwards denied allegations that he had fathered a child with Hunter for more than two years, until 2010, when he acknowledged he was the father of Frances Quinn Hunter.

Elizabeth Edwards separated from John, and died shortly after from breast cancer in 2010.

"I hurt people who didn't know Elizabeth but loved her from afar. I hurt people who gave their hard earned dollars to a campaign - a cause they believed in. I hurt people who are married and believe in marriage. Many of these people have let me know that I hurt them," Hunter wrote today.

John Edwards was brought up on charges in 2012 that he used campaign money to cover up his affair with Hunter, but he was acquitted on one count in 2012.

Hunter wrote in her Huffington Post piece that she realized now she hurt people by writing a tell-all book about her affair with Edwards, and decided to release an amended version now in order to include her regrets and mistakes.

"Owning your past mistakes is no day at the beach but I do believe it is an important endeavor to undertake," she said.