Brad Cooper: "I Cheated. But So Did She."

In an affidavit filed Wednesday, the husband of the murdered jogger in North Carolina tells about his troubled marriage, saying that he cheated, and claiming that his wife did too.

"Three years ago, I made a mistake while married to Nancy. I had a single indiscretion and slept with another woman one time," said Cooper. "I deeply regretted [and still regret] that it happened."

Brad does not disclose the name of the woman he had the affair with in the affidavit, but in an affidavit filed by his wife's friends, the woman is identified at Heather Heider-Metour.

Nancy Cooper's friends and family have pointed fingers at her husband since her body was found. They say he was abusive to her, denying money for things her and the children needed. They say he even threatened suicide at one point, though he denies that.

In his affidavit, Brad states that Nancy had an affair herself about the same time he revealed his indiscretion. "Nancy admitted that she also had an extramarital relationship while married to me, four years ago," Cooper said in the document. "Nancy insisted that she did nothing wrong, that her relationship with the other man only happened once, it wasn't sexual and that no one even knew his name."

The Coopers were attending marriage counselling, but in April 2008, Nancy prepared a separation agreement. As of her death, Brad had not signed the agreement.