You agreed to stick it out through sickness and health and for richer or poorer, but marital vows don't address the other big things that can untie your knot - boredom, feeling out of touch - or worse, platonic friendship instead of an in-love partnership. While honeymoon headiness will inevitably decline, that doesn't mean your relationship has to nosedive as well. In fact, some of marriage's best highlights - raising a family and developing a deeper, more profound connection - require years of togetherness.
Fortunately, there are many things you can do to ensure your relationship stays strong over time. We talked to experts who studied the habits of the happiest couples for their top bonding tips.
Shake up date night
Weekly dinners at your favourite bistro won't stoke your passion, says social psychologist Arthur Aron. According to his research, novelty is the spice of life - and a key ingredient of a good marriage. You don't have to give up your favourite couple-time activities, but do make an effort to inject some new plans into the mix: a hike, a cooking class, or even amusement park rides qualify.
Just pick something you've never done before together. Rewarding experiences flood your brain with dopamine, a mood-boosting chemical. "If your partner is present, that feeling becomes linked to him," says Aron.
Ask this question every day
"How was your day, hon?" Yep, it sounds cliche, but if this nightly ritual has fallen off your radar after years of marriage, consider bringing it back. Sharing this little chat every night really can improve your relationship, says psychologist Angela Hicks. She's found that couples who discuss recent positive events with each other feel happier the next day, with increased feelings of intimacy and connection to their partners.
Laugh over inside jokes
Your teens may groan when you start in on the "good old days," but insider moments only the two of you appreciate is healthy for your bond. In one US study, experts asked 52 couples to reminisce about fun times they had experienced both alone and together; those who liked to recall shared laughs were most satisfied with their relationships. "When people laugh at the same thing, they validate each other's opinions," says lead author Doris Bazzini. "And inside jokes or pet names - things others just don't 'get' - strengthen ties between couples." Bonding over these moments builds a reservoir of joyful memories that can serve as a buffer against tough times.
Don't freak out over a fight
If you've been under each other's skin more than usual, it's not necessarily time to panic or rush to a marriage counsellor. Feeling irritated with one another is almost always a sign that you're healthfully engaged, not drifting apart, according to a US study. "It means you've become comfortable expressing yourself over time," says study co-author Kira Birditt. "Relationships that are close and positive can also be very irritating." That said, if you or your spouse resorts to name-calling or frequent yelling, such behaviour may be a sign of a problem worth addressing.
And when you do argue, fight right
Resolving a marital dispute without damaging your relationship may boil down to a single choice of words. When researchers recently studied disagreements among 154 couples (all married 15 or more years), they found that pairs who used plural pronouns - such as we, us, and our - during an argument were more likely to express positive feelings and report less mental stress afterward. Conversely, those who preferred using "I" during a spat were more likely to have negative emotions and report marital dissatisfaction. "Using 'we language' during a disagreement may help couples align themselves on the same team, as opposed to being adversaries," says lead investigator Benjamin Seider.
Sweat with your spouse
Working out with your husband kills two big birds with one healthy stone: You'll likely get fitter, which benefits your sex life too. One study found that 94% of couples stuck to a fitness program when they did it together, which makes perfect sense. You can keep each other motivated, and it's exciting to explore new fitness activities, like biking or hiking, together. Other research shows that women enjoy sex more when they're physically active - workouts relieve stress, boost energy and give body confidence a lift, all great for your libido.
Celebrate each other's successes
Do you smile when your partner comes home with a pat on the back from his boss or nudges his golf handicap down a point or two? Good, say psychologists, because the way you receive your significant other's exciting news may be even more important than how you react during a crisis. In a study of 79 couples, partners who shared excitement for each other's achievements ("Your hard work is paying off" versus "Can you handle that responsibility?" in response to a promotion, for example) had the most satisfying relationships. Interestingly, how a partner reacted to tough times wasn't as closely tied to satisfaction. A celebration provides the opportunity to boost his ego and reinforce your status as a team, say the authors, so break out those champagne flutes and start saluting yourselves more often.
Listen. Don't just wait to talk
Men get the bad rap for never listening, but admit it: You can probably use a bit of a refresher course too. In fact, Harvard researchers say that couples who express the most empathy and affection are most likely to stay together for the long haul. To become a better listener, try these tips from marriage counsellor Harville Hendrix:
1. Be a mirror. When your partner expresses his or her feelings, show that you're listening by paraphrasing. Start with "Let me see if I've got that: You feel..."
2. Resist the urge to interrupt. "Instead of 'Are you through now?' try 'Is there more to that?' " says Hendrix. "This shows your partner that he or she can feel open and safe with you." Of course, saying it calmly helps too.
3. Validate his POV. Finish with "I can imagine that because of [fill in the situation], you feel [angry, sad, guilty, etc.]."
Get closer to his friends
Of course you're tight with the couple friends you share, but we bet your partner has close work friends or basketball buddies you don't know too well - and research suggests you should. The more a couple's friends and family intermingle, the happier spouses are, according to research that examined the social circles of 347 couples. "Including your spouse in your network of friends is nearly as important for marital happiness as making him feel like a part of your family," says expert Kenneth Leonard, a professor of psychiatry. Women benefited a bit more than men, possibly because they put a higher value on relationships, says Leonard.
Rekindle romance in bed
Last - but most certainly not least - staying intimate and romantically connected is one of the surest things you can do for a happy lasting marriage. While getting things back on track isn't always as simple as splurging on a new negligee or booking a bed-and-breakfast getaway, many experts agree that simply putting sex back on your radar can help - the more you do it, the more you'll want to.