Elizabeth Edwards: “I Only Knew About a Single Night”

Elizabeth Edwards stayed with her cheating hubby because she needs him and "really believes he needs me" too, she said today.

"I do love him," she said.

The wife of philandering husband Sen. John Edwards told Matt Lauer on the "Today" show that if she knew initially that her hubby was having a long-term affair with another woman rather than just a one-night stand she would have resisted his running for president again.

"I only knew about a single night, a single moment of weakness," she said. "I probably would have been more adamant about his not running."

The cancer survivor, who will soon release her memoir  "Resilience" said she didn't leave Edwards because she made a vow to stick by his side and still believes he is a great man.

"The big reason (I stayed) is that I promised I was with him for better or for worse -- this was a lot worse than I ever expected," she said. "Except for this very big thing that he had done ... I believed I was married to a magnificent man. ...He made this one mistake so do I throw out all the good stuff and say only this matters?"

Edwards said her husband was a "marvelous father" who "really cared for [her]" when she was sick.

Though Edwards requested that Lauer not make reference to her hubby's mistress by name, she indicated the pair could rise above the past infidelity.

"I see in the way he looks at me and cares for me that this relationship is the essential relationship of his life -- as my relationship with him in the essential relationship of mine," she said.

She also said that if her husband's alleged love child with longtime mistress Rielle Hunter turned out to be his it would be no further betrayal in her eyes.

"The betrayal happened -- whatever the consequences were," she said. "That's not like a further betrayal that I need to deal with."

She also referred to "parasites" who leech onto others to gain publicity in a subtle reference to Hunter, who Elizabeth Edwards has alleged in the past has jumped on the Edwards couple's coattails to get celebrity status.

Edwards said she believed her husband didn't use campaign funds illegally on Hunter's behalf, defending the Senator's claims that his finances were wholly on the up-and-up.

"The way campaign funds are distributed is all a matter of record. Anybody who wants to see can go on the Internet," she said. "It's just not possible."

Edwards also discussed her cancer, which she said has spread to her thigh. She still deals with aches and pains from the disease, she said.

She ended the interview on a high note, saying she and her husband will persevere through their struggles.

"It's easy to get through the good days. When bad things happen, you have the strength to face them," she said.