15 secrets of happy couples

Your wedding anniversary is a lovely date to remember, but it's not the only milestone that matters. It's even more intimate to celebrate less public moments of which only you two know the true meaning, such as your first kiss, first vacation together or -- hey -- even the first time the pregnancy test turned blue.

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Sure, you have funds earmarked for bills and savings, but every couple also needs a just-for-fun account to fund the occasional, much-need indulgence, says Brown University psychiatry professor Scott Haltzman, M.D., author of The Secrets of Happily Married Men "Put some money aside that won't destroy your budget when you use it," he says. Spend it on a spur-of-the-moment weekend trip, a pricey bottle of champagne or front-row tickets to a concert you're dying to see.

When you two can communicate volumes with a mere raised eyebrow or a barely perceptible nod, you feel like co-conspirators in a sexy suspense film. Stephanie McGuire, 36, of Chicago, shares a very specific expression with her husband when she wants to exit a social situation without hurting anyone's feelings. "It's a really straightforward look with the eyebrows raised quickly," she says. "I don't think anyone else would pick up on it, and it makes us feel closer when we're stuck in one of those 'Get me out of here!' moments."

The first task facing all young couples is separating from their families of origin, points out San Francisco-area-based family researcher Judith Wallerstein, Ph.D. This doesn't mean you shouldn't go home for the holidays. But if there's a crisis over whether to have a second child or relocate for a new job, or even if there's good news about a big raise or the results of a medical test, the couple should talk about it together first before dialing Mom. "You wouldn't believe how many people who are getting divorced say to me, 'She was never mine,' or 'His mother always came first,'" Dr. Wallerstein observes.

It's no secret that most women continue to do more in the housekeeping and child-rearing departments than their partners. Still, when couples become double-entry bookkeepers, adding up every dish washed and every diaper changed, they may be headed for trouble. "Most couples think they should strive for a relationship that's 50-50," observes Manhattan-based family therapist Carolyn Perla, Ph.D., "but the fact is, they should each give 150 percent. In good relationships, couples give everything they can.

Humor, as many psychotherapists have observed, is the Krazy Glue that keeps a couple together. When a couple can no longer laugh together, says Thomas Moore, Ph.D., best-selling author of Care of the Soul, it's a signal that the soul has gone out of their relationship and they are headed for trouble. But Dr. Moore is quick to point out that lighthearted couples never mock each other. They instinctively know what is -- and isn't -- fair game.

You don't have to do the deed every day -- or every seven days, for that matter -- to have a great relationship. But there's no way around this fact: "The happiest couples have sex on a regular basis," says Tina Tessina, Ph.D., author of How to Be a Couple and Still Be Free.  Avoiding a sex drought is crucial, because healthy sex reinforces and deepens closeness. That said, there's no need to stress if you sometimes let a week or two go by without sex. What's key is that you're both happy with your number.

Warning: "Expressing anger by never being in the mood will doom your sex life," says Tessina. Why? Besides the fact that it turns what should be a loving and giving act into a commodity, once sex becomes part of a couple's power struggle, so much resentment builds that soon neither partner wants sex. So instead of feigning fatigue or rolling away from your guy next time you're annoyed, speak up and clear the air — without sex being on the table.

"One of the hardest things to do is to transition from, say, paying bills to being sexy with each other," says Tessina. Successful couples find remarkably unremarkable ways to snap each other out of daily grind mode. How? They figure out their own shorthand for "let's be sexy together." Maybe your man stretches out on the sofa after the kids are in bed and invites you to hop up next to him. Or you swat his butt. Or say, "Gosh, there's nothing on TV tonight, I wonder how we could ever fill the time?!"'

"The main reason marriages break up is not conflict, communication problems, or sexual incompatibility," says relationship researcher Terri L. Orbuch, Ph.D., who followed 373 couples for over 22 years as part of a marriage study funded by the National Institutes of Health. "It's frustration -- the day-to-day disappointment of the gap between what you expect and how your partner acts -- that is most damaging." To diffuse that frustration, share your expectations with each other. "And be sure to check in with your partner once a year, as added pressures or life changes can create new expectations," Orbuch says.