Some of the problem is with the research design. When you're told that you may be interviewed again later, you're going to be less likely to admit an affair, for fear your spouse will learn of it, than if the survey is a one-time truly anonymous contact. From what I see, there has been no reduction in the number of affairs. This is not the worst thing that can happen in a marriage - most people, especially those being left, feel that divorce is even worse. Also the death of a beloved spouse or of a child is worse.
Many affairs mark a turning point in the marriage - with work the marriage becomes much better.
Communication about what you're feeling is even more important in a marriage than communication about what you're thinking. One study shows that for every negative remark by a spouse, it takes 6 positive remarks to make up for it. Couples heal by starting to talk straight with each other about their emotional selves. A great many couples have hidden their deepest emotions, feeling that they're not important enough, or that the other person will be upset. The tasks of rebuilding your marriage are honesty, giving yourself a voice, being vulnerable with your spouse, making your expectations realistic, taking responsibility for your own actions.