How can you possibly decide, out of millions of possible candidates, that a particular individual is the right mate for a lifetime?

Question 1: Can We Talk?

I could only think of one group to ask: people who made the choice and stayed happily married for 50, 60, 70 years and more. My interviews with America's elders (described in more detail here) revealed three key questions you must ask to determine whether the person you are considering is actually the best match for you. And if you fail to ask them, the elders say, you have only yourself to blame if things don't work out.

So before things get too serious, be sure to pose these questions. If the answers are "no," it may be time to move on.

Long-married people say the first question to ask is: Can you talk to this person about everything?Or are there "de-militarized zones" that are off-limits for your conversation as a couple? It may be okay if one partner declares a minor topic off-limits (reality shows or shoe sales, for example). But as a rule, your future partner simply must be someone you can talk to openly and without fear of being judged. Indeed, the most frequent source of "buyer's remorse" in the elders' marriages was finding that a spouse just wouldn't communicate.

Justin, age 85, told me:

A happy marriage is only going to happen if you sit and talk about things. You can't let them boil up inside you and then all of a sudden it blows up. You have to put the fire out when it first starts. So if something comes to mind and you feel like it's been bugging you, then you need talk it out. But too many times people just hold things back and never say anything. I'd recommend that young couples work on this right from the start. In fact, it's something you should learn when you're dating

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According to our elders, the strong, silent type may be intriguing and attractive -- but rarely makes for a great marriage.

Question 2: Do We like Each Other's Family?

The elders don't mince words, and when it comes to future in-laws their advice is clear: If you don't like your prospective partner's family, think twice about marriage. Taking a close look at potential in-laws is an important safeguard against making the wrong choice. First, they say that your partner's family and how he or she interacts with them can provide important "diagnostic" information about him or her. Second, you will have a very long period of interacting with this "second family."

William, 86, put it bluntly:

Question 3: Can We Be Friends?

Here's the situation. If one of the families is definitely against their child's choice of a mate, you can get married, no problem. But if the in-laws to be don't like the mate, they're going to be continually sniping at the person and eventually, unless the person you marry is awfully strong, the family is going to win. It can lead to divorce, it can lead to isolation of your marital unit, and it can just cause an untold amount of grief.

According to the elders, you are not just marrying a person -- you are marrying a family. So ask yourself honestly if you can live with problematic relatives for a lifetime.

If you ask a long-married person: "What's the secret to a long, happy marriage such as yours?" you are almost sure to hear a variant of "I married my best friend." Similarly, from elders whose marriages did not succeed, I often heard: "Well, we were good lovers, but we never learned how to be friends." In addition to romance, you need to have some of the qualities of friendship: shared interests, the ability to empathize and commiserate, the capacity to comfortably hang out with one another.

Lydia, age 75, put it eloquently:

Be friends, like each other. It's hard when you're young and hot on one another to back off and say, "Do I like what is behind these hands and these body parts?" But that is the piece that doesn't wear out, that grows and deepens. The sexual aspect deepens too, in its own way, but it becomes less important and the friendship becomes more important as the years go by. It will be challenged by kids and hardships and losses of parents and changing interests and patterns, but an abiding friendship is at the base of a solid marriage.

Therefore, as a relationship is moving into a serious phase, ask each other: If we weren't in love, would we be friends? And if not, think twice about moving ahead.

There's no perfect method or algorithm for choosing a mate. But according to the elders, taking a step back and asking these three questions about your relationship can help you avoid a tragic mistake -- or move you toward a long, fulfilling life together.

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