What Makes Love Last? Introduction
Angel: I have something to say—

George: Hold on. I’m not finished.

Angel: What I am trying to say—

George: See and this is what I’m talking about—

Angel: Right, I know, because I do not—

George: You cut in—

Angel: I have to say something now—

George: No. Because when you cut in—

Angel: I have something to say here.

George: SHUT UP!

Angel and George were newlyweds juggling long work hours while raising two toddlers. That’s a situation tough enough to put pressure on any marriage, but you wouldn’t need a background in research psychology to recognize that this one was in trouble. The dialogue above is a snippet of the argument they had in my research lab. They sparred without end over who worked harder, who did more housework and who said what when. Angel and George, like many embattled couples, gave up on their marriage and divorced. This outcome was not unexpected considering how damaged their relationship was. When I met with them, they could barely look at each other without scowling and rolling their eyes.

For years I have invited couples like Angel and George to take part in experiments at my “Love Lab,” the media’s nickname for the facility at the University of Washington in Seattle, where I subject long-term romance to scientific scrutiny. In a typical study I analyze couples while they converse about everyday topics as well as when they argue. I interview them together and individually. I’ve even observed couples while they spend an entire day at the Love Lab’s studio apartment, which comes complete with sofa, loveseat, TV, kitchen, a lake view, and video cameras hooked to the walls, which record every moment of their interactions. (The bathroom, of course, is off limits.) Thanks to these studies, I have accumulated nearly four decades’ worth of data—a library of how and what partners say to and about each other, and their physiological reactions. These days I also conduct similar exercises with couples who are not part of any study but wish to receive a scientific assessment of their relationship’s staying power.

When couples like Angel and George enter the Love Lab, we hook them up to enough sensors and wires to elicit quips about Dr. Frankenstein. While they adjust to the equipment and their surroundings, information begins to stream from the sensors, indicating their blood velocities, heart and pulse rates, the amount their palms sweat, and even how much they squirm in their chairs. A video camera records all of their words and body movements. On the other side of a one-way mirror, my assistants, surrounded by equipment readouts, and the requisite collection of empty cola cans, scrutinize the subtle interplay between the couple’s biological reactions, body language, facial expressions, and words.

The most frequent experiment I conduct is called the conflict discussion, in which we ask the couple to converse about an area of disagreement for fifteen minutes. To facilitate the analysis of their facial expressions during their disputes, I train a separate video camera on each of them so I can view their faces in real time on a split screen.

It no longer surprises me when our couples are able to relax and “let it rip” despite the staring cameras. Still, I find that most people do curb their behavior in the lab compared to when they squabble at home. But even when partners are acting “camera ready,” they can’t hide from the accuracy of my sensors.

Close analysis of so many couples over the years led me to formulate seven key principles that can improve the odds of maintaining a positive relationship. Described in The Seven Principles for Making Marriage Work, they emphasize the value of friendship between partners, accepting each other’s influence, and being gentle during disagreements. These fundamentals remain a powerful tool set for all relationships. But the sad fate of couples like Angel and George indicated to me that these principles did not reach deep enough to salvage many damaged romances. I could not accept that these partners were somehow fated to be losers at love. To aid these despairing couples, I needed to better understand what was going wrong between them.

Perhaps what puzzled me most about the unhappy couples I studied or counseled was their sincere insistence that they were deeply in love and committed to their relationship—even as they were ordering each other to “shut up” in the Love Lab. Why did so many self-proclaimed devoted couples engage in constant warfare? It made no sense. They derived no relationship benefits from their quarrels. They reported more distress over fighting than did happy couples—and yet they went at it more often.

It would be easy to assume that the unhappy couples argued more than others because, well, they disagreed more. What could be more logical? But as a scientist, I know that “obvious” conclusions are not always accurate. In my lab, computer scientist Dr. Tara Madyhastha helped me find the answer. To trace the anatomy of interactions between unhappy partners, she used what are called “hidden Markov models.” These types of computer analyses, often implemented to decode languages or DNA sequences, can detect underlying patterns. Her results indicated that couples who seem to act like adversaries rather than lovers are trapped by what is known, in technical terms, as an absorbing state of negativity. This means the probability that they will enter the state is greater than the odds that they will exit it. In other words, they get stuck. These unlucky partners are imprisoned in a roach motel for lovers: They check in, but they can’t check out. Consumed by negativity, their relationships die there.

Understanding why some couples wind up in this terrible trap while others are able to sidestep it has been at the heart of my recent research. As a result, I have developed a new understanding of couple dynamics and an enhanced approach to bettering all romantic relationships—not just the ones in distress.

If you listened to trapped couples argue in my lab, you would hear a litany of complaints that wouldn’t seem to have much in common. Tim grouses that Jane cares more about her mother’s opinion than his. Alexis keeps stalling on starting a family, to the frustration of her husband. Jimmy doesn’t like it that Pat wants to switch churches. But when I speak to these unhappy partners, I am struck by an underlying similarity. They are all talking (or shouting) past each other or not even bothering to communicate at all. Despite their commitment to sticking it out, they have lost something fundamental between lovers, a quality often termed “magic” or “passion,” that exists at a primitive, “animal” level. That’s why they end up in the roach motel.

I now know that a specific poison deprives couples of this precious “something” and drives them into relentless unhappiness. It is a noxious invader, arriving with great stealth, undermining a seemingly stable romance until it may be too late. You’ll think at first that I’m stating the obvious when I tell you that the name of this toxin is betrayal. I recognize that some of the harm wrought by betrayal is common knowledge. We face a constant onslaught of tabloid “gotcha!” stories about celebrities and politicians with sex addictions and broken marriage vows. These morality tales of distrust and disloyalty underline how common and devastating infidelity can be. Yet I have good reason for calling betrayal a “secret” relationship killer. The disloyalty is not always expressed through a sexual affair. It more often takes a form that couples do not recognize as infidelity. In my lab, partners will insist that despite their troubles they have been faithful to each other. But they are wrong. Betrayal is the secret that lies at the heart of every failing relationship—it is there even if the couple is unaware of it. If a husband always puts his career ahead of his relationship, that is betrayal. When a wife keeps breaking her promise to start a family, that is also betrayal. Pervasive coldness, selfishness, unfairness, and other destructive behaviors are also evidence of disloyalty and can lead to consequences as equally devastating as adultery.

Despite how dangerous and widespread betrayal is, I can offer couples hope. By analyzing the anatomy of this poison, I have figured out how to defeat it. I now know that there is a fundamental principle for making relationships work that serves as an antidote to unfaithfulness. That principle is trust. Once again it might sound like I’m trumpeting the obvious! Happy couples tell me all the time that mutual trust is what lets them feel safe with each other, deepens their love, and allows friendship and sexual intimacy to blossom. Unhappy partners complain that their relationship lacks this element. But all couples tend to think of trust as an intangible quality that can’t be pinned down or measured in a concrete way. In fact, it is now possible to calculate a couple’s trust and betrayal levels mathematically and subject them to scientific study. This new analytical approach allows me to identify a couple’s strengths and vulnerabilities, and to devise strategies that can rescue miserable relationships from the roach motel and keep others from going there.

In addition to benefitting couples, this new understanding of trust and betrayal has profound cultural implications. It has become commonplace for us to increase the complexity of our lives until we almost reach the breaking point. With our emails, cell phones, and intricate juggling of responsibilities, we live on the edge of a catastrophic stress response. We each have our own “carrying capacity” for stress and tend to pile it on till we come just shy of overload. Headlines that hawk “stress cures” are rife on the internet, on newsstands, and in bookstores. But I believe trust is the greatest stress buster of all.

In relationships where there is a high potential for betrayal, people waste time and emotional energy. Whether the fear concerns adultery or other faithlessness, suspicious people act like detectives or prosecuting attorneys, interrogating their partners, looking for verification that their insecurity is justified. Decision making becomes exhaustive and exhausting: If I go out of town, will he leave the kids with that babysitter I don’t trust? If I check her closet, am I going to find new clothes despite our austerity budget? Should I risk confrontation by checking out his story? One man who suspected his wife of cheating put chalk marks on her rear tires before he left for work one morning. Later, when he discovered that the chalk marks were no longer visible, indicating the car wheels had turned, he asked whether she had left the house. Forgetting about her morning dash to the post office, she said no. This prompted a jealous rage, which put both of their stress levels into hyperdrive.

In sharp contrast, trust removes an enormous source of stress because it allows you to act with incomplete information. You don’t subject your mind and body to constant worry, so the complexity of your decision making plummets. You don’t need to put chalk on tires or otherwise test your partner. Implicit trust saves you a lot of time and leaves you free to grapple with less tumultuous concerns.

I always strive to increase the understanding of long-term relationships and to help couples navigate their way to happier and healthier romance. Still, I know that not all relationships can, or should, survive betrayal. Even when a long-term partnership ends for good reason, the shattered faith in love can be devastating. The loss must be acknowledged and confronted before moving on. If you are recovering from a breakup, the findings and exercises in the pages ahead may offer a deeper understanding of what went wrong and help prepare you to try again with somebody new.

Charting a way forward after a deep wound is just as important as learning to make a relationship work. If your last relationship failed, you may fear trusting someone again. But this wariness can leave you vulnerable to lifelong and profound loneliness. This isolation has not only serious psychological repercussions but physical ones as well. By fine-tuning your radar for deception, this book can help you develop the courage, strength, and wisdom to search for a trustworthy partner.

Throughout my career I have met skeptics who do not believe that sensors, computers, video cameras, and other lab equipment can assess something as mysterious and seemingly indefinable as love. Of course, scientists cannot create a love potion or a solution to all relationship woes. But I can offer advice founded on objective data rather than unproven theory or just the subjective experience of a particular therapist. The pages that follow offer the fruit of my research. They explain why romances can fail for reasons that seem as elusive as love itself. I hope you’ll use my findings to protect a thriving relationship or to rescue one already in danger.