Elizabeth Edwards’s appearances on "Oprah" last week and on "Today" with Matt Lauer Monday morning continue to inspire questions about her motives. Why is she staying with her husband if she is clearly still angry with him? Why is she airing her dirty laundry – or, in the words of Tina Brown on The Daily Beast, why has she “fed herself to the vultures,” by writing and talking about her husband’s affair?

Regarding the first question, it turns out that she is more like the majority of Americans than we might think – statistics show that most marriages survive infidelity. “A great many relationships are successful at navigating through it and prospering afterward,” says Dr. Brad Sagarin, a professor of social psychology at Northern Illinois University. “Infidelity does not automatically erase the love that was there. Undoubtedly there is a lot of anger, but it doesn’t negate all the positive feelings. It is wise not to make an immediate decision to dump the marriage because often the desire to stay often ends up outweighing the initial angry desire to leave.” 

Not all couples that stick together “prosper,” of course – it takes hard work for that to happen. “Marriages survive infidelity one of two ways,” says Mira Kirshenbaum, a Boston-based couples’ therapist and author of When Good People Have Affairs. “In one case it’s a result of the wronged spouse having nowhere else to go. The marriage survives but the relationship dies. They simply carry on carrying on. In the best case, the relationship goes into intensive care, but comes out of it better than ever.” For that to happen, she says, “the cheated-on spouse must have the capacity to forgive and the cheater must have the sincere desire to earn forgiveness by truly seeing and understanding and feeling the pain he’s caused.”

The cheated-on spouse must also face some hard truths. "In therapy, we let the wronged spouse get angry and rail," says Manhattan-based clinical psychologist Jeff Gardere, who is also a frequent commentator on the "Today Show." "But at one point you have to say, ‘Now let’s look at where you may have had some responsibility, in terms of the choices you made or why you may have decided to look the other way. If you don’t confront that, you will either get into a new relationship that is a carbon copy of the old one, or your spouse is going to go right back out and do it again.’"

I have no idea if  David Vitter, the Louisiana senator who was a client of the DC Madam (and reportedly also a frequent client of a now-shuttered New Orleans house of prostitution), got therapy with or without his wife, but I do remember Wendy Vitter’s gutsy handling of the situation when they made the de rigueur march to the podium. Rather than remaining mute and smiling like so many before her, she took the microphone from her husband and said, “To forgive is not always the easy choice. But it was the right choice for me. David is my best friend.” While there is no accounting for taste, I believed her – and, like the Harts and the Spitzers and, so far, the Edwardses, they are still together.

As for the second question – why would Elizabeth Edwards air this out? – she’s not alone in that either. When former New Jersey governor Jim McGreevey announced his “truth,” that he was a “gay American,” Dina McGreevey, his wife and the mother of his child, stood – smiling! – beside him. Then, after the shock wore off, she wrote a book, Silent Partner, detailing her hurt and her anger, and including the tidbit that before she accompanied him to the podium he told her that “you have to be Jackie Kennedy today,” and that she should “smile a little more” during the part when he planned to ask for forgiveness.