With Valentine’s Day approaching, I’ve started to think about how I might celebrate with my husband of 27 years—and about our relationship in general. We’ve always enjoyed being romantic, but we’ve also settled into a more comfortable routine with fewer surprises.

That’s not necessarily a bad thing, but there’s always room for nurturing our passion for one another and keeping our relationship strong. Loving, committed relationships require ongoing effort, just like staying in shape requires regular trips to the gym.

Enter relationship experts Suzann Pileggi Pawelski and James Pawelski. In their book, Happy Together, they’ve combed through research to identify four keys for keeping love alive in relationships: promoting healthy, harmonious passion (as opposed to obsession); cultivating and prioritizing positive emotions, rather than just waiting for them to happen on their own; savoring positive emotions, rather than letting those moments slip by; and finding ways to nurture your partner’s strengths.

At a Greater Good Science Center event on March 22, The Science of a Happy Relationship, the Pawelskis will expound on these keys, sharing (along with other speakers) how couples can nurture a passionate connection and improve their chances of staying together. I spoke with the Pawelskis recently about the challenges for long-term relationships and how to cope with them more effectively—including how to celebrate Valentine’s Day.

Jill Suttie: What do you think are some of the primary challenges in a lasting, committed relationship?

Suzann Pileggi Pawelski: One of the main problems is that people tend to focus on the challenges and the problems too much. Problems scream at us, right? When you have something that’s annoying you—whether it’s a toothache or something your partner is doing or saying—you tend to dwell on that. And, unfortunately, small wonderful moments—opportunities to connect or say a small thank you—get skipped over. We might not even notice those moments because we’re moving so quickly in life. 

James Pawelski: There’s also a lot of focus these days on finding your “soulmate.” If by soulmate you mean somebody that you’re deeply connected to, we have no problem with that. But oftentimes the notion of soulmates takes on a kind of magical, mystical quality—at some point you’ll find your other half or somebody who will “complete you”. That’s a dangerous proposition, because that implies that there’s nothing I can do to have a good relationship—it’s either going to happen or it won’t.

It can also lead us to think that another person is going to somehow make us magically happy. If I rely on Suzie to make me happy, that’s not fair to Suzie because she is her own person, with her own goals and directions in life. If our relationship is dependent on her making me happy, then that’s probably not going to be very sustainable. Research indicates that it’s really interdependence that we want to have with another person—not complete dependence or, the opposite, complete independence. We want to be interconnected.

JS: How do shared positive emotions play a role in relationships?

SPP: We know from positive psychology research that positive emotions feel good and they’re good for us. There are multitudes of positive emotions in relationships—not just the jumping-up-and-down, ebullient ones most commonly portrayed in the media, but things like serenity and gratitude, awe, and inspiration.

Barbara Fredrickson’s research shows that as relationships evolve, there’s a continuum along which we experience emotions. They start out with the high-arousal ones, like joy and interest, and that’s great and wonderful. However, sadly, many relationships peter out once the couple is no longer experiencing these high-arousal emotions at such a high frequency. Some people abandon the relationship at this point. However, researchshows that as relationships develop and mature, you also experience the calmer, more grounding emotions, like gratitude and inspiration and ultimately love, if the relationship is long-lasting.

Of course, it’s important to be there for your partner during hard times, too, like when your partner loses a job or there’s a death or something serious. However, the research shows it’s just as important, if not more important, for couples to celebrate the good times. Those who do have more successful, long-lasting relationships.

JS: What’s a practice you might recommend that gets at one of your four keys?

SPP: How about a “strengths date”? It’s something we do ourselves and recommend to couples all of the time.

JP: To do a strengths date, you first identify your top five strengths, commonly referred to as your signature strengths, based on the classification of strengths and virtues created by Christopher Peterson and Martin Seligman—things like curiosity, gratitude, kindness, or love of learning. You can take the free online VIA Survey that helps you to identify your signature strengths, those strengths that are natural for you.

Then, you can create a particular outing or date where you’re able to use strengths from each person. Instead of saying to your partner, “I like watching sports—so, Suzie, this week you’re going to have to watch sports with me even if you hate it, and next week we’re going to go watch a film that I really don’t like, but you’ll like,” the idea is to find one date that can allow both of you to put your natural strengths to action. For example, one of Suzie’s strengths is zest, and one of mine is love of learning. For a strengths date, we took a Segway tour of historic Philadelphia, and she was able to enjoy riding around in a Segway, while I was delighted to learn about the history of the city.

SPP: My love of adventure was satisfied and James’s love of learning was piqued—it was more than just satisfied. And that’s good, because the research shows when we do things that we’re intrinsically motivated by, it increases our individual well-being. And when we help facilitate strength use in our partners, it leads to greater relational satisfaction and greater sexual satisfaction. We’re not saying you should never do something that your partner wants to do and you don’t. But if you’re doing that all the time, it’s kind of like taking turns being happy instead of being happy together.

JS: As we’re approaching one of the big romance-centered holidays of the year—Valentine’s Day—do you have any recommendations for how couples celebrate?

JP: There are a lot of marketers who want us to buy things on Valentine’s Day, and we can sometimes miss what it’s about. So, I’m going to add some philosophy here. Aristotle had some interesting things to say about types of relationships: Some are focused on usefulness or mutual benefit, and some are based around pleasure—it’s just fun to be with that person—and there’s nothing wrong with those kinds of relationships. But there’s a third kind that is even more profound, even more mature, and that’s a relationship based on appreciating the goodness in the other person.

So, our recommendation for Valentine’s Day might be to focus less on what you receive from your partner or on what fun it is to be with that person, and instead focus on the goodness in that person and their character. What do you really appreciate about who they are? Then, you can express that appreciation and also support your partner as they continue to develop those good character qualities.

JS: I’m imagining skeptics saying that’s all well and good, but by looking for the good in relationships, aren’t you ignoring real problems?

SPP: I just want to make a disclaimer here: Of course, if you’re in an emotionally or physically abusive relationship, you have to leave for psychological or physical safety. Sometimes a relationship is not salvageable, and it shouldn’t be. But we’re talking here about ordinary relationships, with typical arguments.

JP: And we aren’t saying that if you don’t have severe issues, you shouldn’t acknowledge or be aware of problems at all, either. It’s just that in most relationships, we can get into a cycle of focusing only on problems and can’t see anything else. Not only is that inaccurate—because there are good sides along with the downsides of any relationship—but it also makes it really hard to develop and grow. When you’re focused on the negative only, you’re less likely to see opportunities and solutions. Focusing on the good parts of the relationship puts us into a state of mind from which it’s much more likely that we will be able to address challenges in ways that we can make positive changes.

JS: Is there evidence that focusing on the positive in this way helps couples remain together and feel closer?

SPP: Absolutely. The research shows that couples often break up not only because of huge problems, like affairs or whatnot, but because over time they no longer feel acknowledged or appreciated—and often, sadly, end up feeling they are being taken for granted. In contrast, research shows that savoring our partner and his or her qualities may be more effective at communicating our love than a variety of other means, like gift giving, doing chores, etc.

Continually showing and expressing gratitude for each other builds intimacy and strengthens bonds over time. Gratitude is probably one of the most important, if not the most important, positive emotion and strength when it comes to relationships. In fact, couples in which both members acknowledge their partner and express appreciation for all the good things their partner does for them are 50 percent more likely to stay together.

Part of the reason we are trying to help couples grow the good and notice the good is that good things actually happen to us more frequently or at a higher ratio—we just don’t notice them. We let them slip by. If you’re just focusing on problems and fixing them, but not growing the good, that’s a problem. Relationships are like a garden, metaphorically: If you’re picking the weeds, you’re not going to have any more weeds. But if you didn’t plant seeds for the flowers, you won’t have flowers, either.

Originally published in Greater Good Magazine.

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