Why Good People Cheat

South Carolina Governor Mark Sanford's June 24 statement that his yearlong affair with an Argentine woman began "innocently" has drawn both sympathy and scorn. Can you really have good intentions and still wind up in bed with someone other than your spouse? Mira Kirshenbaum, a couples' counselor and the author of When Good People Have Affairs, says the answer is yes. She talked to TIME about why people cheat and how a broken marriage can be repaired. (See the top 10 political sex scandals.)

You argue that the majority of people who have affairs are actually good people who just made a mistake. Isn't that letting them off the hook?
No. They're good people because they really are suffering. And they don't know what to do. They want love in their life, [and] they feel that there's something radically wrong and they don't know how to correct it.

You note that 47% of men and 35% of women get involved either emotionally or sexually with someone other than their spouse. Do you think one type of affair — emotional or physical — is more dangerous than the other?
No. If the other person would feel betrayed, then it's an affair, whether it's emotional or sexual. It's surprising: some people feel less betrayed by a sexual affair than they do by an emotional one. (Read why some couples don't get married.)

Is one type of affair easier for a marriage to bounce back from?
It depends. If both people want their marriage to survive, the key is for the cheating spouse to make sure he earns forgiveness, and not just by saying he's sorry and showing remorse. He has to do the time-consuming work of listening — for hour after hour, if necessary — to how much and in how many ways he has hurt his spouse. He has to commit to understanding what she needs to feel safe in the future, and to doing those things. And they both have to commit to healing the broken parts of their marriage and revitalizing it. (Read about marriage savers.)

You advise people never to confess to their partner that they've had an affair, even if they're asked point blank. But won't they miss out on that process of forgiveness?
There are many people who have no talent for forgiveness. It's as if they're frozen in this betrayal for years and years. If [you plan to stay in the marriage], why would you tell your spouse something that's going to devastate her and make it so much harder to heal? Couples end up talking for hours about every little detail. They want to know: Did you go there with her? Did you do this with him? The conversation becomes about a past that can't be changed. And it's heartbreaking. Don't ever lie again. But do not confess to an affair.

In his press conference on Wednesday, Governor Sanford said that his affair began "innocently." Do you think affairs really can begin in an innocent way?
They most often do. You're friends with someone, you're just hanging out, you're getting to know them, and then you find yourself having feelings. We all have feelings, but you don't have to act on them. (Read about Sanford's sex scandal: assessing the damage.)

Reality stars Jon and Kate Gosselin have also made headlines recently for their marital woes. Do you think people in the public eye tend to cheat more often than the rest of us, or do we just hear about their indiscretions more frequently?
Based on all the studies I've seen, roughly half of all marriages will be touched by an affair at some point. The prevalence of affairs is a function of two things: less-than-happy marriages and opportunity. And these celebrities have many more opportunities than most people. (See the top 10 skanky reality TV shows.)

You also argue that affairs can be good for a marriage. What do you mean?
They're a wake-up call. They tell you there's something seriously wrong here [and] you can't go on with business as usual. And if you really listen and you take that seriously and act on it, then you have an opportunity to make something wonderful happen.

Speaking of working on a marriage, you write that there are only two stages in a relationship: ignorance and rehab. That sounds pretty cynical. What do you mean?
At the beginning everyone is on their best behavior, so you're really ignorant of the ways [the relationship is] not going to work. You take care of the problems that can be solved easily at the beginning. [Later on in the marriage] you have to keep making sure that you're paying attention to your most important needs and make sure you're getting them met. (Read about the science of romance.)

So you're not saying marriage is miserable?
Not at all. I've been married for a really, really long time. And just because people have problems doesn't mean they can't solve their problems. I work with so many couples who have gone through all the stages of dealing with this stuff and they come out the other end in a much better place than they ever were. I guess what I want to leave people with is the hope that you will take love seriously. It's the best thing in life. Why would you say it's too hard?

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