What's the key to a lasting marriage?

A recently released study from the Australian National University polled 2,500 couples in search of the keys to long-lasting relationships, and they came up with some not-so-surprising tidbits.

For example, women who want children much more than their spouses are more likely to get a divorce. And, roughly 16 percent of men and women whose parents ever separated or divorced were also more likely to split, unlike 10 pecent of those whose parents weren't apart.

Also, partners who are on their second or third marriage are 90 percent more likely to separate than first-timers.

And of course, money plays a major role, too. Up to 16 percent of those who said they were poor or where the husband (not the wife) was unemployed have separated, compared with only nine percent of couples in good money shape.

So, for those of us without these major obstacles already in our way or for those who want to get past them, how do you make a marriage or a long-term relationship more lasting?

My grandmother used to say that the key to the happiness of her multi-decade marriage to my grandfather was simply, "Never go to bed angry with each other." And according to Shae Graham Kosch, PhD, who teaches behavioral medicine at the University of Florida, grandma wasn't far off.

"Most marital conflicts don't ever get resolved," she says. "What's crucial is keeping things positive. You have to accept the other person's perspective, have an appropriate discussion without getting critical or blaming."

In searching for more tips on what helps keep couples together (PDF), I found these from Carolyn Gerard, a marriage and family therapist:

• Prioritize time with your partner: Set aside time to be together, and manage problems before they come between you.
• Be careful how you “start up” a conversation: Before launching into sensitive topics, "stop and think about what you’re feeling and what you hope to accomplish." Is the confrontation really about fixing the relationship, or is it more selfish or hurtful?
• Pay attention to your partner’s bids for connection: Don’t take your spouse for granted; give him the attention he deserves.
• Exit an argument before it gets out of control: This doesn't mean walking away entirely. Just make sure you're attacking the problem, not each other.
• Remember the “Five to One” Rule: "In a happy marriage, couples make five times as many positive statements to and about each other and their relationship than negative ones."

I also love this advice from Susan Boon, PhD, a psychologist at the University of Calgary. "You have to do nice things often. But it's harder to be nice when the heat is on, when you're really angry.... [T]he balance must be heavily, heavily stacked in the positive, to have a happy marriage."

What do you think are the keys to a happy marriage? Do you agree with the tips the experts provided here? Share your thoughts in the comments below!