Editor's note: This article originally appeared in the May 24, 2014 Gwinnett Daily Post. It has been reprinted here with permission.

Several readers have asked me, "Where does love come in? Isn't it foundational to a good marriage?"�

Yes, it is but not in the way you might think. Love is not a cornerstone but rather the sum total of all four cornerstones. It's an action verb, not a passive noun, manifesting itself through all the behaviors we've been talking about, like compatibility and commitment.

That's especially true of this cornerstone, service, which philosophers and spiritual leaders have long regarded as the highest manifestation of love. Essentially, service is love in action: doing for others what they're not in a position to do for themselves, seeking to make their lives as easy and fulfilling as possible without regard for our own selfish desires.

Most of us assume that when people go out of their way to serve others, it must be because they love them. But the truth is that we don't just serve the people we love; we come to love the people we serve.

Think about your children. Why do you love them so much? Sure, they're your flesh and blood but what about parents who adopt children and come to love them just as if they were their own? Isn't it possible that we love our children so desperately because we spend so much time and effort serving them, especially when they're young?

Now apply that same reasoning to marriage. When you were newly married, your strong feelings of personal fondness and sexual attraction made you want to do things for each other in order to demonstrate those feelings - and perhaps to elicit some reciprocity.

But, those emotions tend to fade over time; at best, they ebb and flow. So what do you do when you're not feeling particularly "in love"? Do you simply stop doing things for each other?

The answer is, yes, that's exactly what most of us do. We stop going out of our way to serve each other. And that's a major reason so many marriages stagnate and ultimately break down.

What we ought to be doing - what we MUST do if we really want to enjoy a happy and lasting marriage - is just the opposite: the less "in love" we feel, the more we need to serve each other. Because the more we serve each other, the more we come to love each other.

I know that sounds counterintuitive, but I would invite you to put it to the test. Of course, it works better when both spouses participate - when both are equally intent on putting each other first and serving each other.

Unfortunately, that won't always be the case. Sometimes you just have to show your love by serving your spouse, whether your efforts are reciprocated or not.

That's kind of what love means.