Recent statistics suggest that 40% of women (and that number is increasing) and 60% of men at one point indulge in extramarital affairs. Put those numbers together and it is estimated that 80% of the marriages will have one spouse at one point or another involved in marital infidelity.

That may seem like a very steep number. However after two decades plus of full time work as a marriage and family therapist, I don't believe that number is off the charts. I worked with a great number of people involved in infidelity who were never discovered.

The possibility that someone close to you is or soon will be involved in an extramarital affair (any of the three parties) is extremely high.

Maybe you will know. You will see telltale signs. You will notice changes in the person's habits and behavioral patterns as well as a detachment, lack of focus and reduced productivity. Maybe you will sense something "out of character" but be unable to pinpoint what it is.

It is not a given that he/she will tell you. Those hiding the affair will continue to hide. The "victim" of the extramarital affair often, at least initially, is racked with anger, hurt, embarrassment and thoughts of failing that preclude divulging the crisis.

It might be important to confront the person with your observations, depending on the status of your relationship with the person.

It is important to understand that extramarital affairs are different and serve different purposes.

Out of my study and experience with hundreds of couples I've identified 7 different kinds of infidelity.

Briefly, some extramarital affairs are reactivity to a perceived lack of intimacy in the marriage. Others arise out of addictive tendencies or a history of sexual confusion or trauma.

Some in our culture play out issues of entitlement and power by becoming "trophy chasers." This "boys will be boys" mentality is subtly encouraged in some contexts. Some become involved in marital infidelity because of a high need for drama and excitement and are enthralled with the idea of "being in love" and having that "loving feeling."

An extramarital affair might be for revenge either because the spouse did or did not do something. Or the revenge may stem from rage. Although revenge is the motive for both, they look and feel very different.

Another form of infidelity serves the purpose of affirming personal desirability. A nagging question of being "OK" may lead to usually a short-term and one-person affair. And finally, some affairs are a dance that attempts to balance needs for distance and intimacy in the marriage, often with collusion from the spouse.

The prognosis for survivability of the marriage is different for each. Some affairs are the best thing that happens to a marriage. Others serve a death knell. As well, different extramarital affairs demand different strategies on the part of the spouse or others. Some demand toughness and movement. Others demand patience and understanding.

The emotional impact of the discovery of infidelity is usually profound. Days and weeks of sleeplessness, rumination, fantasies (many sexual) and unproductivity follow. It typically takes 2 4 years to "work through" the implications. A good coach or therapist can accelerate and mollify the process. I don't recommend "marriage" counseling, at least initially.

The devastating emotional impact results from a couple powerful dynamics. Trust is shattered of one's ability to discern the truth. The most important step is NOT to learn to trust the other person, but to learn to trust one's self. Another is the power that a secret plays in relationships. THE secret exacts an emotional and sometimes physical toll that needs to be acknowledged and dealt with.

How can you help?

Those in the midst of their affair crisis told me they need this from you:

1. Sometimes I want to vent, get it out without censor. I know sometimes I will say what I shouldn't be saying. It may not be nice, pretty or mild. Please know that I know better, but I need to get it off my chest.

2. Every so often I want to hear something like, "This too shall pass." Remind me that this is not forever.

3. I want to be validated. I want to know that I am OK. You can best do that by nodding acceptance when I talk about the pain or confusion.

4. I want to hear sometimes, "What are you learning? What are you doing to take care of yourself?" I may need that little jolt that moves me beyond my pain to see the larger picture.

5. I may want space. I may want you to be quiet and patient as I attempt to sort through and express my thoughts and feelings. Give me some time to stammer, stutter and stumble my way through this.

6. I want someone to point out some new options or different roads that I might take. But before you do this, make sure I am first heard and validated.

7. When they pop into your mind, recommend books or other resources that you think I might find helpful.

8. I want to hear every so often, "How's it going?" And, I may want this to be more than an informal greeting. Give me time and space to let you know exactly how it IS going.

9. I want you to understand and welcome the ambivalent feelings and desires. I would like you to be fairly comfortable with the gray areas and the contradictions about how I feel and what I may want.

10. I want you to be predictable. I want to be able to count on you to be there, listen and speak consistently or let me know when you are unable to do that. I will honor that.

Extramarital affairs are powerful. Affairs are costly. They affect family, friends, colleagues and employers. Infidelity is also an opportunity to redesign one's life and love relationships in ways that create honor, joy and true intimacy.