Friend of presidential candidate's wife testifies about days before her death.

When Elizabeth Edwards first learned of a National Enquirer expose revealing her husband's affair, her reaction was "volcanic" and she fretted that John Edwards' infidelities would "humiliate" her and end his campaign, a campaign pollster testified today.

ohn Edwards put his head in his hands and his daughter Cate left the courtroom in tears today as a former aide testified about how Edwards' wife became distraught when she found out that he was still having an affair with mistress Rielle Hunter. Elizabeth Edwards "collapsed in a ball" in an airport parking lot and tore off her shirt in a fit of anger, the witness said.

Up until John Edwards officially claimed paternity of his mistress's daughter, his dying wife Elizabeth clung to his lies that he was not the father and on her death bed lamented that she would die alone because of his indiscretions, a friend testified today. It was poignant testimony on one of the last days of the prosecution's case, but the day included a surprise as well. Although much of the trial hinges on Edwards' relationship with his lover Rielle Hunter, the prosecution said it would rest its case Thursday without calling Hunter as a witness.

Prosecution of John Edwards wraps by playing ABC News interview.