what does Jimmy Carter have in common with Ozzy Osbourne?

I often give President Carter a hard time as one of our worst presidents.

But he and Ozzy deserve kudos for this-- their marriages, especially in a time when marriage has been diminished by a casual approach to what should be sacred.

Here's Elizabeth Bernstein in the WSJ...

For Ozzy and Sharon Osbourne, it's perseverance. For Jimmy and Rosalynn Carter, it's maintaining separate work lives....

OK, maybe it wasn't always bliss. But each of them has stayed married—to the same person—for a very long time. And each considers his or her marriage to be happy, strong and mutually supportive. In other words, they beat the odds....

James Cordova, a psychologist at Clark University, advises couples not to leave it to chance. You should assess your marriage at least once a year, he says. "Imagine going to the dentist only if your tooth actually hurt. At that point something has gone terribly wrong, and the odds of saving it go way down," says Dr. Cordova, author of "The Marriage Checkup." "Marriage is the same."

Of course, no one ever said that every day, or even every year, was going to be rosy. And there are plenty of long marriages that are unhappy. But there are some strategies that happily married couples say work:

• Find the middle ground.

• Be funny.

• Keep (some) secrets.

• Never, ever give up.