In 2001, when I was 28, I broke up with my boyfriend. Allan and I had been together for three years and there was no good reason to end things. He was (and remains) an exceptional person, intelligent, good-looking, loyal, kind.

My friends, many of whom were married or headed towards marriage, were bewildered. I was bewildered. To account for my behaviour, all I had were two intangible yet undeniable convictions: something was missing and I wasn't ready to settle down.

The period that followed was awful. I barely ate for sobbing all the time. I missed Allan desperately. On good days, I felt secure that I'd done the right thing. Learning to be alone would make me a better person, and eventually a better partner. On bad days, I feared I would be alone forever. Had I made the biggest mistake of my life?

Ten years later, I occasionally ask myself the same question. Today I am 39, with too many ex-boyfriends to count and, I am told, two grim-seeming options to face down: either stay single or settle for a "good enough" mate.

At this point, certainly, falling in love and getting married may be less a matter of choice than a stroke of wild great luck.

A decade ago, luck didn't even cross my mind. I'd been in love before, and I'd be in love again. This wasn't hubris so much as naïveté; I'd had serious, long-term boyfriends since I was a teenager and simply couldn't envision my life any differently.

Well, there was a lot I didn't know 10 years ago. The decision to end a stable relationship for abstract rather than concrete reasons ("something was missing"), I see now, is in keeping with a post-Boomer ideology that values emotional fulfilment above all else.

And the elevation of independence over coupling ("I wasn't ready to settle down") is a second-wave feminist idea I'd acquired from my mother, who had embraced it -- in part, I suspect -- to correct for her own choices.

Sins of the mother

Once, as a teenager, driving home from a family trip, my mother turned to my boyfriend and me cuddling in the backseat and said, "Isn't it time you two started seeing other people?"

She adored Brian -- he was invited on family holidays! But my future was to be one of limitless possibilities, where getting married was something I'd do when I was ready, to a man who was in every way my equal, and she didn't want me to get tied down just yet.

This unfettered future was the promise of my time and place.

I spent many a golden afternoon at my small New England liberal-arts college debating with friends the merits of leg-shaving and whether or not we'd take our husband's surname.

Even then, our concerns struck me as retro -- hadn't the women's libbers tackled all this stuff already?

We took for granted that we'd spend our 20s finding ourselves, whatever that meant, and save marriage for after we'd finished our education and launched our careers, which of course would happen at the magical age of 30.

That we would marry, and that there would always be men we wanted to marry, we took on faith. How could we not?

One of the many ways in which our lives differed from our mothers' was in the variety of our interactions with the opposite sex.

Men were our classmates and colleagues, our bosses and professors, as well as, in time, our students and employees and subordinates -- an entire universe of prospective friends, boyfriends, friends with benefits, and even ex-boyfriends-turned-friends.

In this brave new world, boundaries were fluid and roles constantly changing.

What my mother envisioned was a future in which I made my own choices. I don't think either of us could have predicted what happens when you multiply that sense of agency by an entire generation.

Are men now redundant?

As women have climbed ever higher, men have been falling behind. We've arrived at the top of the staircase, finally ready to start our lives, only to discover a cavernous room at the tail end of a party, most of the men gone already, some having never shown up.

Those who remain are leering by the cheese table, or are, you know, the ones you don't want to go out with.

In the 1990s, Stephanie Coontz, a social historian at Evergreen State College in Washington, noticed an uptick in questions from reporters and audiences asking if the institution of marriage was falling apart.

She didn't think it was, and was struck by how everyone believed in some mythical Golden Age of Marriage and saw mounting divorce rates as evidence of the dissolution of this halcyon past.

She decided to write a book discrediting the notion and proving that the ways in which we think about and construct the legal union between a man and a woman have always been in flux. What Stephanie found was even more interesting than she'd originally expected.

In her fascinating 'Marriage, a History: From Obedience to Intimacy, or How Love Conquered Marriage', she surveys 5,000 years of human habits, from our days as hunters and gatherers up to the present, showing our social arrangements to be more complex and varied than could ever seem possible.

Stephanie came to the conclusion that marriage was undergoing a transformation far more radical than anyone could have predicted, and that our current attitudes and arrangements are without precedent. "Today, we are experiencing a historical revolution every bit as wrenching, far-reaching and irreversible as the Industrial Revolution," she wrote.

Last summer, I spoke to Stephanie about this revolution. "The transformation is momentous -- immensely liberating and immensely scary," she told me. "When it comes to what people want and expect from marriage and relationships, and how they organise their sexual and romantic lives, all the old ways have broken down."

For starters, we keep putting marriage off. We're also marrying less -- with a significant degree of change taking place in just the past decade and a half.

Even more momentously, we no longer need husbands to have children, nor do we have to have children if we don't want to. A childless single woman of a certain age is no longer automatically perceived as a barren spinster.

Do I want children?

Of course, between the diminishing external pressure to have children and the common misperception that our biology is ours to control, some of us don't deal with the matter in a timely fashion.

Like me, for instance. Do I want children?

My answer is: I don't know. But somewhere along the way, I decided to not let my biology dictate my romantic life. If I find someone I really like being with, and if he and I decide we want a child together, and it's too late for me to conceive naturally, I'll consider whatever technological aid is currently available, or adopt.

Do I realise that this further narrows my pool of prospects? Yes. Just as I am fully aware that with each passing year, I become less attractive to the men in my peer group, who have plenty of younger, more fertile women to pick from.

But what can I possibly do about that? Sure, my stance here could be read as a feint, or even self-deception. By blithely deeming biology a non-issue, I'm conveniently removing myself from arguably the most significant decision a woman has to make.

But that's only if you regard motherhood as the defining feature of womanhood -- and I happen not to.

By themselves, the cultural and technological advances that have made my stance on childbearing plausible would be enough to reshape our understanding of the modern family -- but, unfortunately, they happen to be dovetailing with another set of developments that can be summed up as: the deterioration of the male condition.

The decline of men

Men have been rapidly declining -- in income, in educational attainment and in future employment prospects -- relative to women.

And while the rise of women has been good for everyone, the decline of males has obviously been bad news for men -- and bad news for marriage.

For all the changes the institution has undergone, modern women as a whole have never been confronted with such a radically shrinking pool of what are traditionally considered to be "marriageable" men -- those who are better educated and earn more than they do.

So women are now contending with what we might call the new scarcity.

Even as women have seen their range of options broaden in recent years -- for instance, expanding the kind of men it's culturally acceptable to be with, and making it okay not to marry at all -- the new scarcity disrupts what economists call the "marriage market" in a way that in fact narrows the available choices, making a good man harder to find than ever.

At the rate things are going, the next generation's pool of good men will be significantly smaller.

What does this mean for the future of the family?

In their 1983 book, 'Too Many Women? The Sex Ratio Question', two psychologists developed what has become known as the Guttentag-Secord theory.

It holds that members of the gender in shorter supply are less dependent on their partners, because they have a greater number of alternative relationships available to them.

How this plays out, however, varies drastically between genders.

In societies where men heavily outnumber women -- in what's known as a 'high-sex-ratio society' -- women are valued and treated with deference and respect and use their power to create loving, committed bonds with their partners and raise families.

When confronted with a surplus of women, men become promiscuous and unwilling to commit to a monogamous relationship.

In societies with too many women, the theory holds, fewer people marry, and those who do marry do so later in life.

Because men take advantage of the variety of potential partners available to them, women's traditional roles are not valued, and because these women can't rely on their partners to stick around, more turn to extra-familial ambitions such as education and career.

As a woman who spent her early 30s actively putting off marriage, my anecdotal findings have revealed that, yes, in many cases, the more successful a man is (or thinks he is), the less interested he is in commitment.

Take the high-powered magazine editor who declared on our first date that he was going to spend his 30s playing the field.

Or the prominent academic who announced on our fifth date that he couldn't maintain a committed emotional relationship but was very interested in a physical one.

Or the novelist who, after a month of hanging out, said he had to get back out there and tomcat around, but asked if we could keep having sex anyhow, or at least just one last time.

And those are just the honest ones.

To be sure, these men were the outliers -- the majority of my personal experience has been with commitment-minded men with whom things just didn't work out, for one reason or another.

Marriage o'clock

Indeed, another of my anecdotal-research discoveries is of what an ex calls "marriage o'clock" -- when a man hits 35 and suddenly, desperately, wants a wife.

I'll never forget the post-first-date email message reading: "I wanted to marry you last night, just listening to you."

Nor the 40-ish journalist who, on our second date, driving down a long country road, gripped the steering wheel and asked, "Are you The One? Are you The One?" (Can you imagine a woman getting away with this kind of behaviour?)

Like zealous lepidopterists, they swoop down with their butterfly nets, fingers aimed for the thorax, certain that just because they are ready for marriage and children, I must be, too.

I remember experiencing a panicked exhaustion around the time I turned 36, at which point I'd been in the dating game for long enough, and I wanted out.

I'd spent the past year with a handsome, commitment-minded man, and these better qualities, along with our having several interests in common, allowed me to overlook our many thundering incompatibilities. In short, I was creeping up on marriage o'clock, and I figured, enough already -- I had to make something work.

When it became clear that sheer will wasn't going to save us, I went to bed one night and had a rare dream about my (late) mother.

"Mom," I said. "Things aren't working out. I'm breaking up with him tomorrow."

"Oh, honey," she said. "I am so sorry. We were rooting for this one, weren't we? When something doesn't work, though, what can you do?"

This, I found irritating. "Mom. I am getting old."

"Pwhah!" she scoffed. "You're fine. You've got six more years."

Six more years. I woke up. In six more years, I'd be 42. All this time, I'd been regarding my single life as a temporary interlude, one I had to make the most of -- or swiftly terminate, depending on my mood.

Now that 35 had come and gone, and with yet another relationship up in flames, all bets were off. It might never happen. Or maybe not until 42. Or 70, for that matter.

Was that so bad? If I stopped seeing my present life as provisional, perhaps I'd be a little ... happier. Perhaps I could get down to the business of what it means to be a real single woman.

Embracing the single status

Famous Bolick family story: When I was a little girl, my mother and I went for a walk and ran into her friend Regina. They talked for a few minutes, caught up. I gleaned from their conversation that Regina wasn't married, and as soon as we made our goodbyes, I bombarded my mother with questions.

"No husband? How could that be? She's a grown-up! Grown-ups have husbands!"

My mother explained that not all grown-ups get married. "Then who opens the pickle jar?" (I was five.)

Thus began my lifelong fascination with the idea of the single woman. There was my second-grade teacher, Mrs Connors, who was, I believe, a former nun, or seemed like one.

There was the director of my middle school's gifted and talented programme, who struck me as wonderfully remote and original. (Was she a lesbian?)

There was a college poetry professor, a brilliant single woman in her 40s who had never been married, rather glamorously, I thought.

When I embarked on my own sojourn as a single woman in New York City -- talk about a timeworn cliché-- it wasn't dating I was after.

I was seeking something more vague and, in my mind, more noble, having to do with finding my own way, and independence. And I found all that.

Early on, I sometimes ached, watching so many friends pair off, and without a doubt there has been loneliness.

At times I've envied my married friends for being able to rely on a spouse to help make difficult decisions, or even just to carry the bills for a couple of months.

And yet I'm perhaps inordinately proud that I've never depended on anyone to pay my way. Today, that strikes me as a quaint achievement, but there you have it.

Once, when my father consoled me, with the best of intentions, for being so unlucky in love, I bristled. I'd gotten to know so many interesting men and experienced so much. Wasn't that a form of luck?

Now that women are financially independent, and marriage is an option rather than a necessity, we are free to pursue what the sociologist Anthony Giddens termed the "pure relationship", in which intimacy is sought in and of itself and not solely for reproduction.

In the months leading to my break-up with Allan, my problem, as I saw it, lay in wanting two incompatible states of being -- autonomy and intimacy -- and this struck me as selfish and juvenile.

I was too ashamed to confide in anyone and, as far as I could tell, mine was an alien predicament anyhow -- apparently, women everywhere wanted exactly what I possessed: a good man; a marriage-in-the-making; a "we".

So I started searching out those who, like me, had gone off-script.

No men allowed

I definitely noticed an increase in my own contentment when I began to develop and pay more attention to friendships with women who, like me, have never been married. Their world views feel relaxingly familiar, and give me the space to sort through my own ambivalence.

The sense of community we create puts me in mind of the 19th-century availability of single-sex hotels and boarding houses, which were a necessity when women were discouraged from living alone, and then became an albatross when they finally weren't.

So last year, inspired by visions of New York's 'women only' Barbizon Hotel in its heyday, I persuaded my childhood friend to take over the newly available apartment in my building in Brooklyn Heights.

We've known each other since we were five, and I thought it would be a great comfort to us both to spend our single lives just a little less atomised. It's worked.

These days, I think of us as a mini-neo-single-sex residential hotel of two. We collect one another's mail when necessary, share kitchenware, tend to one another when sick, fall into long conversations when we least expect it -- all the benefits of dorm living, without the gross bathrooms.

Could we create something bigger and more intentional?

In August, I flew to Amsterdam to visit an iconic medieval bastion of single-sex living. The Begijnhof was founded in the mid-12th century as a religious all-female collective devoted to taking care of the sick.

The women were not nuns, but nor were they married, and they were free to cancel their vows and leave at any time. Over the ensuing centuries, very little has changed.

Today, the religious trappings are gone (though there is an active chapel on site), and to be accepted, an applicant must be female and between the ages of 30 and 65, and commit to living alone.

I contacted an old boyfriend who now lives in Amsterdam to see if he knew anything about it and he put me in touch with Ellen, an American friend who has lived there for 12 years.

The bliss of living single

The Begijnhof is big -- 106 apartments in all -- but, even so, I nearly pedalled right past it on my rented bicycle, hidden as it is in plain sight: a walled enclosure in the middle of the city, set a metre lower than its surroundings.

Inside was an enchanted garden -- a modest courtyard surrounded by classic Dutch houses of all different widths and heights. Roses and hydrangea lined walkways and peeked through gates. The sounds of the city were indiscernible.

A writer and producer of avant-garde radio programmes, Ellen (60) has a chic, minimal style that carries over into her little two-floor apartment, which can't be more than 300sq ft.

Neat and efficient in the way of a ship, the place has large windows overlooking the courtyard and rooftops below. To be there is like being held in a nest.

We drank tea and Ellen talked about how the Dutch don't regard being single as peculiar in any way -- people are as they are. She feels blessed to live at the Begijnhof and doesn't ever want to leave. Save for a few friends on the premises, socially she holds herself aloof; she has no interest in being ensnared by the gossip on which some of the residents thrive -- but she loves knowing that they're there.

Ellen has a partner, but since he's not allowed to spend the night, they split time between her place and his nearby home. "If you want to live here, you have to adjust, and you have to be creative," Ellen said.

When an American woman gives you a tour of her house, she leads you through all the rooms. Instead, this expat showed me her favourite window views: from her desk, from her (single) bed, from her reading chair.

As I perched for a moment in each spot, trying her life on for size, I thought about the years I'd spent struggling against the four walls of my apartment, and I wondered what my mother's life would have been like had she lived and divorced my father.

A room of one's own, for each of us. A place where single women can live and thrive as themselves.

© 2011 The Atlantic Media Co. A longer version of this article first appeared in the Atlantic Magazine. Read the full version here. All rights reserved. Distributed by Tribune Media Services

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