If you’ve been married awhile, you may find that you and your spouse have settled into a comfortable routine. Maybe you even take each other for granted. But some people who have been happily married a long time have a surprising secret—they treat marriage as if it were a lifelong date.

That came from Cornell University gerontologist Karl Pillemer, PhD, author of 30 Lessons for Loving: Advice from the Wisest Americans on Love, Relationships, and Marriage. He learned it from a 70-year-old woman named Leigh. Leigh and her husband agreed to treat their marriage as a lifetime date.

Here’s why it works: When we go on dates, we do our best to be interesting, upbeat, attractive and attentive. We put forth our best selves and try to make the person we’re with feel special.

When we’ve been married a long time, we take our partners for granted. We don’t feel the need to make an effort, because after all, we know that they love us, so why do we need to? But we do need to, explained Pillemer. When we make an effort, we fuel the spark that makes a marriage thrive.

Another aspect of dating is that it’s exciting because it offers an element of the unknown. Long-term relationships can lose their spark when they become predictable. Married couples who regularly try new things together…take spontaneous trips…offer compliments out of the blue…and give gifts at unexpected moments increase their odds of remaining happily married forever.

Treating a marriage like a date does not mean that there won’t be trying times. The trick is to view the difficult days of a marriage like the time between dates—not as a problem with the relationship but as an unavoidable intermission from it. Then we look forward to when we can resume the date of our lifetime.

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