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I AM CURLED UP ON THE SOFA, ready for a DVR marathon of my favorite shows—when my iPhone presents me with a slew of new Facebook updates. A group of girlfriends is also catching up on episodes of New Girl and Revenge, but they are all together ... with wine ... just a few miles away. Before you waste your sympathy on me, the shunned friend, you should know that I was actually invited to the TV viewing party. I chose not to go. It was a perfectly sensible decision given the circumstances (weather: awful; workload: massive). So why, when presented with uploaded photographs of my friends having fun, did I suddenly feel panicky? As though I'd missed out on something infinitely more important than sharing laughs over the antics of Jess Day and Emily Thorne and too much red wine on a school night? What revelations or connections were made? Opportunities presented? What other plans could develop out of this one evening? The mind reels.

I can, at least, take comfort in the knowledge that this form of social anxiety is common. It's been discussed so often recently that it even has its own acronym: FOMO (fear of missing out). The symptom? A nagging suspicion, fueled by the forensic details of other people's lives we are privy to on social media, that our own existences are somehow lacking. If only we'd made the right decisions, we berate ourselves, we'd have the fascinating careers/relationships/opinions/offspring/social lives that we perceive others all around us to have.

Canvassing other women on the issue, I discover that many of my friends are also wrestling with FOMO. Holly, a 30-year-old TV producer, tells me, "I spend far too much time worrying about what others are doing. Media people love using Facebook and Twitter to show off, so I have this constant sense that I'm not in the loop—not doing the cool thing. I have this ridiculous feeling that if I could just behave a bit more like them, then I'd suddenly become some kind of Oscar-winning director. It's as though other people have this magic formula for a successful life that is eluding me."

Meanwhile, Katy, 34, a nurse, says FOMO has her worried that she's missed the opportunity to have kids. "I've risen up the ranks fast, and I love my job," she says. "As a result, I guess I haven't exactly prioritized my relationships, and they've all fizzled. Recently I've been spending more and more time analyzing my friends' lives, mostly via social networking sites, and questioning decisions I made in my 20s. If I'd gotten to know such-and-such guy better, would I be the one tweeting about which school my kids had made it into?"

So many of us, in fact, proclaim ourselves plagued by the ghosts of "what might have been" that renowned psychoanalyst Adam Phillips has devoted his latest book, Missing Out: In Praise of the Unlived Life, to the subject. "As we know more now than ever before about the kinds of lives it is possible to live—and affluence has allowed more people than ever before to think of their lives in terms of choices and options—we are always haunted by the myth of our potential," Phillips writes. "Our lives have become an elegy to roads not taken."

So how exactly do we stop wasting precious time fretting about what else is out there? Jessica Chivers, author and life coach, agrees that FOMO is a growing problem for modern women. Part of the issue is the number of choices available to us, she says. We are told that plenty of choice is a good thing—and, of course, all of us facing this dilemma are lucky. But in psychological terms, it isn't necessarily positive. "This is well studied by psychologists," says Chivers. "When presented with lots of choices, we become much less efficient at making decisions and less happy with the decisions we make. If I put you in a supermarket aisle with nine different types of cornflakes, you would enjoy your breakfast less than if you had to buy the only brand they stocked."

Yet, says Chivers, far from being a disaster, missing out opens up pathways previously hidden from us. She uses the example of getting passed over for a promotion. "You feel it was your time," she says. "Your skills were right, you were in the right place mentally—of course you feel aggrieved about not getting the job. But it is in just these situations that people often make great career moves. The act of preparing yourself for the job, even though you didn't get it, has moved you on mentally. You'll begin to see opportunities that you were blind to before."

And if you find yourself daydreaming about what could be, it turns out that's not entirely unhealthy. "Daydreaming isn't a way of opting out of 'real life'—it's a safe place to explore possibilities," says Chivers. "You may reject most of the things you fantasize about in that you won't actually do them, but that editing process is vital to our mental well-being. When we have explored options and rejected some in favor of others, then we develop what psychologists call an internal locus of control. In other words, we feel that we are masters of our own destiny."

The takeaway: No worries, no regrets, no matter what everyone else is up to. Or at least, the ability to simply catch up on your DVR queue in relative peace.

How to let go of FOMO:
1. Step away from your computer or smartphone. Social media fuels FOMO, so if you're a Facebook and Twitter addict, allow yourself the occasional information detox.

2. Accept you can be in only one place at a time. If you're going to do one thing, then acknowledge this will mean missing out on other things. People who excel miss out all the time--they just don't worry about it.

3. Cut down on the amount of time you spend researching alternatives. Too much choice is not necessarily a good thing. If an option works for you, stick with it.

4. Recognize, however, that the first option to come up may not be the best for you. Be discerning in your decision-making. No need to say yes right away.