(OPRAH.com) -- I've been practicing psychotherapy for more than 30 years, and in my view a great number of people are running around thinking that they are depressed when it may be that they are simply disappointed.

Expert: A mature relationship doesn't begin until after disappointment.

Not that disappointment is merely a case of depression lite. It can cast heavy shadows over one's life, often with lasting consequences, especially when it occurs in love or career. As the character played by Shirley MacLaine in The Evening Star (the sequel to Terms of Endearment) put it, "Disappointment has ruined more lives than all the diseases known to man."

But it's not disappointment that ruins lives. It is the incapacity or the refusal to deal with life after disappointment.

There are plenty of roads that can lead to disappointment. But probably the heaviest traffic turns up on the one traveled by people in search of love.

Consider the plight of Shelley and Franklin, a couple in their mid-30s who came in together to see me for marital therapy. They had found each other six years earlier at a mutual friend's book party. Both were glamorous professionals moving steadily forward in their careers -- he as a creative young scholar at a major university who also writes a literary column for the Sunday edition of a newspaper, she with a big job in the media, producing documentary films for a national cable channel.

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When their eyes first met, the din of the party seemed to recede and the room to light up for the two of them with a glow of promise. After a few months of Friday and Saturday nights together, they moved in with each other. Within a year, marriage felt right to both of them.

But marriage turned out to be a good deal more than they had bargained for. As singles living together, they'd conducted their lives separately. When they dined together, it was usually in restaurants.

Now someone had to shop and cook, clear the table and do the dishes. The garbage had to be taken out every night. Piles of bills mounted. There was the question of who got to sleep through the night and who was on call when their new baby's colic kicked up at 2 a.m. It became more and more difficult to find time for sex. They were both too tired anyway.

No such thing as a perfect union

Resentments accumulated between these two busy professionals. Everyday demands overwhelmed their earlier vision of married life: a dream of four or five decades of thriving careers interspersed with romantic evenings and weekends. From the beginning of courtship through the initial excitement of moving into one or the other's small apartment, from the wedding ceremony through the honeymoon, being newly in love tends to hide or at least blur two people's differences -- particularly differences in needs for sex, for intimate time together, for autonomy and time apart, for planning and organization, for control over finances, for being with the children, and for freedom from parenting -- in just about everything.

The extraordinary experience of romantic love conveys the feeling that "the two of us are as one." But the daily tasks of marriage can quickly disabuse a couple of the notion that they have found such a perfect union.

As their different rhythms and preferences emerge in the course of living together, each comes to feel that the other is not, after all, the ideal partner who brings salvation from loneliness, deprivation, a sense of personal inadequacy, or other anxieties of the solitary self. "You are not who I thought you were," they tell each other. And from the depths of this disappointment, they often turn to accusing each other of deception, selfishness, or worse.

If you were to experience Shelley's and Franklin's unhappiness individually, you might think they both were depressed. But in my office, they reeled off their disappointments to each other. It was like witnessing a trial between two plaintiffs, each making a case for being the bigger victim, the major sufferer of unmet needs at the hands of the other.

Disappointment is a stage of love nearly every serious intimate relationship -- probably every one that lasts longer than overnight -- has to struggle with. It may strike suddenly or build up slowly, but once the battling begins, it can assume tragic proportions for a couple trying to make a life together. Oprah.com: Meet 3 less-than-perfect couples

The very first disappointment

We don't have to look very far to come upon a captivating tale about disappointment -- it is among our oldest and most familiar stories, the story of Adam and Eve in Genesis. Where else among the world's cultures does one find a creation myth in which human history begins not with magic animals or demigods or occult forces but with newlyweds engaged in doing what so many other married couples since have done: making bad judgments together and then blaming each other for the difficulties that they bring down on themselves.

Despite the best real estate on the planet, peace everywhere, no competition for mates, and all their needs gratified, Adam and Eve cannot leave well enough alone. Once they find something they can't have, they hardly seem interested in anything else. The forbidden apple is too fascinating to resist. Eve at least has the intellectual curiosity and rebelliousness to take the initiative. Adam is too busy being a good boy. When God shows up and demands an explanation, Adam declares that it was the woman's fault. Adam is the first in a long line of passive-aggressive males.

The famous pair wrapped themselves in fig leaves and took to the bushes after the apple made them aware that they were naked. Centuries of theologians have informed us that this discovery signified the first sexual shame. Maybe so, but I have a slightly different take. Adam and Eve had always been naked in Eden. What made the difference?

In the Garden of Eden, nothing changed, nothing grew, nothing died. Time never passed until Adam and Eve learned that the Fall meant that they would eventually die. It's mortality that starts the meter running. And nakedness under the regime of time is significantly different from nakedness before time exists. No more perfect youthful bodies forever. From now on, the hint of a potbelly here, the possibility of a sagging breast there.

In other words, I suspect that when Adam and Eve looked at each other through the filter of time, they were more disappointed than ashamed. "You are not who I thought you were," they might have been the first to say to each other after the revelation that nobody is perfect. But to love is to become aware of loss with further losses to come. I believe that this is among the major reasons that love makes us so anxious.

Falling in love leads to such monumental expectations of happiness that it can feel like the discovery of paradise. But falling out of paradise with regularity also seems to be our lot. What happened to Adam and Eve happens to all of us -- over and over again. There's nothing like thinking that you have failed at love to sharpen your knowledge that life is uncertain and the clock is relentlessly ticking. One tends to ask oneself, "If this relationship won't work, will I ever find one that does?" Disappointment measures the passing of time as a fall. It is one of our harsh reminders of solitude and aging and mortality.

Depression or disappointment

How can we bear to live with it? Here's where the difference between depression and disappointment becomes crucial. Faced with the prospect of loss, the person who gets depressed bypasses disappointment and rushes to the end of the story, even before the story begins. All is failure, decay, and rejection. When spring begins and the buds appear, the depressive is already dreading the leaves turning brown and falling off the trees.

Depression is a withdrawal from life. There is a kind of hubris in this withdrawal, as though being depressed were a way of saying, "this imperfect, difficult world is not good enough for me. Give me paradise or give me death." The philosopher Jean-Paul Sartre pointed out that depression is like a spell that a person casts over the world to make it utterly gray and uninteresting. Then you can tell yourself, "What's the use of trying? Why bother to get out of bed?"

The disappointed person lingers, however painfully, in the middle of the story, even though paradise has slipped through his or her fingers. Disappointment keeps you connected to life as it continues to unfold and places an important choice in front of you. It informs you that time has gone by and things have changed since you first risked investing in a cause or a career or an intimacy with another person. Neither a utopian outcome nor easy success nor bliss in love is just around the corner. Life is more difficult than you thought. The question is, what next? Are you going to take on the vital forces of life, despite limitations and imperfections, or pull the covers over your head as an exit strategy?

A patient of mine, a divorced woman in her 30s, a graphic designer, constantly bemoaned the lack of intimacy in her life. She told me that she was prone to black depressions, particularly on weekends. I found out that she spent weekends alone in her apartment, making no effort to contact the outside world. It was as if she were waiting for a Prince Charming to arrive and sweep her away. Apparently this rescuing figure had to do all the work; she wasn't going to budge.

Behind this repetitious and unpromising pattern lay a history of disappointment at the hands of the key men in her life. Her father had disappeared behind The Wall Street Journal at breakfast, and the rest of the time into his own unhappiness over his failed career aspirations. He didn't even bother to show up at school plays in which she sometimes had leading roles. She married young, having found a man who courted her enthusiastically. But before long he, too, disappeared -- into alcohol. She lost faith that any actual intimacy would meet her needs.

It became necessary to explore her deep disappointment rather than simply treat her depression. Disappointment has a future; depression doesn't. There is no where to go if you are already at the end of the story. With disappointment, the plot is still taking shape, even though there may be hard work to do -- such as, in the case of my patient, learning to tolerate the unknown of the future despite past suffering and to risk rebuilding a social life anyway. Therapy aims at helping people live in the present free from the compulsion to repeat the past, but you often have to dig down to find what gives rise to the repetition. Oprah.com: Are you depressed? Stay in control of your mind

Finding empathy

I am pretty sure that no amount of medication is going to make disappointment much easier to deal with. The challenge is how to live a good life in spite of disappointment. Among the least promising ways is to blame others. Partners who blame each other for what goes wrong in a relationship wind up acting like people pushing past each other to get on a crowded subway or bus, one saying, "I'm late!" and the other replying, "No, I'm late!" The result is an atmosphere of growing tension as the two defend the turf of their separate identities against each other.

What's needed to transform disappointment in a relationship into something livable in the present and useful for the future is that kind of empathy in which two people's selves take a backseat to a shared sense of each other's suffering. It is impossible to be defensive and empathic at the same time.

Empathy helps turn anger into sorrow. When sorrow becomes mutual, it begins to erase the lines drawn in the sand. Only then does the possibility of apology and forgiveness become real.

I consider this sequence -- anger, sorrow, apology, forgiveness -- one of the most important developmental passages in marriage or in therapy with couples because it is a prerequisite for the restoration of innocence. That may sound strange, but what I mean is not the first innocence of childhood or infatuation but a kind of second innocence, innocence after experience, which is free from repetition and thus can treat a new moment as new. Repetition kills love. To experience the next moment with a person as a new moment -- and therefore open to curiosity, surprise, even revelation -- is the heart of love.

A flourishing intimacy is likely to demand an extraordinary amount of empathic and patient cultivation from both partners. Unfortunately, what we experience growing up in our families or viewing ads of gorgeous couples zooming off for ski vacations in their new BMWs does very little to teach us that creating a satisfying relationship is a difficult but worth while discipline, like mastering a craft or an art form. The first drafts of love are usually in need of considerable revision.

Romantic love is beautiful, but no matter how full the moon that first night, no matter how many willows are weeping and birds singing your song, you can't build years of relationship on that lovely, fragile foundation alone. Everything I've learned from my work with people disappointed in love points to this conclusion: A mature relationship doesn't begin until after disappointment. Oprah.com: How to get good at love

By Michael Vincent Miller, Ph.D., from "O, The Oprah Magazine," 2009

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