Originally posted October 23, 2009. Updated February 3, 2020.

Even good relationships are susceptible to the ravages of an affair. That defies expectations, doesn’t it? Yet any therapist specializing in relationships can tell a story or 2 that confirms this statement. Still, with careful positioning and maintenance of the “walls and windows” in our relationships, it is possible to build a strong shelter that nourishes intimacy inside and keeps threats to intimacy out.

Affair proof your relationship: use walls and windows

affair proof your relationship: keep walls around your relationship
keep walls around the two of you

The image of a wall* surrounding each person in a relationship illustrates how we all hold private thoughts and feelings inside ourselves. Partners in healthy relationships promote intimacy with each other by having open windows in their walls through which there is unguarded exchange of personal and private thoughts and feelings. During the course of an affair, the unfaithful partner closes his or her window to their partner, and knocks a new window elsewhere in his or her wall to permit the affair partner in.

All marriages go through dry periods where not much of one’s intimate inner life travels back and forth through the windows, even though the windows to each other are open. At such times our attention may well wander, and so we notice the many fascinating people around us.

Affair proof your relationship: open the window of yourself to your partner
open the window of yourself to your partner

We meet these people at work, at social functions, traveling, and even in our neighbourhood. These others have fascinating stories and charming personalities. We may tell our partners about these fascinating others; we may not. But we will start to feel the crumbling of the wall that is our primary relationship.

Use the window

In this sort of situation, we ought never take the open window to our partner for granted. Use it. Share your feelings and thoughts. Expect the same from your partner. Don’t hesitate to discuss how the window between the two of you seems closed or opaque, or that it’s just not being used. Take the risk and tell your partner that you feel the walls of your relationship crumbling. And yes, take the risk also of telling your partner how susceptible you are to windows opening up in your wall to others.

Affair proof: maintain the windows

Affairs don’t begin with love. They begin with interest and infatuation. They begin when we don’t maintain our walls. A stray sentiment that should be passed through the open window to your partner is instead allowed to seep through a crack in the wall to the fascinating other. Gradually, more thoughts and feelings follow the initial stray one. The crack widens to window size while the window to the committed relationship closes.

So while keeping your window open to a spouse, keep your walls strong when it comes to fascinating others. If you find yourself talking to a fascinating other about matters you ought to be taking up with your partner, you are actively contributing to the widening of the cracks and the deterioration of your walls.

Be honest, you’re not “just friends”

Most people do not set out intentionally to have affairs. Early on, the erring spouse rationalizes, “Oh, we’re just good friends.” But ultimately, infidelity is any emotional or sexual intimacy that violates trust. Research shows that emotional affairs are as devastating as sexual affairs. You can bet that your partner will react with all the intensity that goes with sexual betrayal even if your “friendship” hasn’t crossed that line yet.

Faithful sharing with your spouse about the kinds of events, people, clothes, mannerisms, behaviours that tempt you helps keep your walls and windows functioning.

Don’t let a possible tempest derail you

Afraid of a possible tempest, one person told me how he responded negatively when his wife asked, “Did you notice that woman eying you all night?” He had noticed, but he denied it. He was probably right, too, there would have been a tempest (though perhaps only in a teapot) if he had told his wife that the attention flattered and confused him at the same time. But that discussion–even if it was a tough one–would also have led to a serious discussion that would have increased the flow of thoughts and feelings through the windows the partners had open to each other; and the discussion could have reinforced the importance of have strong walls against the inappropriate sharing of intimacy.


Many kinds of secretive behaviour are symptomatic of serious wall and window issues. Such behaviours might include erasing potentially embarrassing texts; not telling, or “forgetting” to tell your spouse whom you went to lunch with, who is calling you, or who is emailing you; or having a “friend” who knows more about your marriage then your spouse knows about your “friendship.” All behavior that leads to furtive acts or thoughts is a sign that the relationship between you and your spouse is seriously under threat. At times like these, what may have been–or even seem, for now–to be a good marriage needs help. That help can come in the form of partners who brave the tempest to sort matters out, or who seek therapy to help them with window and wall maintenance.

Love alone does not protect a relationship from the havoc of an affair. Strong walls and windows are also needed to protect against external threats to intimacy.

*The walls and windows image comes from Shirley Glass, Ph.D., NOT “Just Friends”: Rebuilding Trust and Recovering Your Sanity After Infidelity. Don’t let this book’s title mislead you. While it is helpful for couples recovering from an affair, it is an invaluable guide for all couples wanting to shield their relationships from the (ever-present) threats to outside intimacy.