Okay, I have an admission to make. When I first tell people I'm not on Facebook there's a moment when perplexed expressions of disbelief, incredulity and downright apprehension cross their faces.
They run the whole gamut. Sympathy – maybe I've been forbidden to join Facebook. Horror – maybe I don't have my own laptop. Fear – maybe they're speaking with a social deviant, one who should be boycotted by friends and banished to social Siberia. Most are too perturbed to ask for my reasons. I, in turn, see no reason to explain. But just for the record, here goes:
Facebook doesn't need me
With more than a billion members and a valuation of $104bn, Facebook is doing fine without me. Its popularity is legend: it was the top search term in 2012 for the fourth year running.
Given the facts, my absence is unlikely to keep Mark Zuckerberg awake at night. He and I are in a perpetual state of mutual impasse. I've resisted all offers to fandango with Facebook and reached sweet 16 without accepting its very many terms of service. For me, that's reason enough for us to keep going our separate ways.
Facebook is a waste of time
Facebook offers me nothing I need. What it can do is waste my time but, for me, that's no draw as I quite enjoy doing that for myself.
If I was on Facebook, chances are I'd probably spend an hour and 20 minutes there each day. That's the average amount of time 18- to 25-year-olds devote to it. It's also time I could use for mastering Tai Chi, brain training or contemplating new ways of eliminating world debt.
While I don't spend it on any of those pursuits, I do spend it laughing endlessly with friends, gingerly applying make-up or playing mind-games with my dogs. What I do with that time mightn't make much of a difference to anyone else, but for me it feels good and my dogs wouldn't have it any other way.
Join Facebook in haste, leave . . .
Let's get this straight. While joining Facebook is easy-peasy, leaving is not a task for the faint-hearted. Facebook, like one particularly covert organisation that has Tom Cruise as a member, can make all efforts to disentangle feel like one giant guilt-trip.
Their methods may be different, but the result is the same – grief. Who needs it?
Facebook is a forum for self-publicising narcissists
Facebook is an exercise in egotism and self-publicity. It's about creating impressions, often with the intention of either wowing or infuriating others.
The very concept leaves me cold, but not half as cold as that of toxic narcissistic personality disorder which, if scientists are to believed, may be the reason why some Facebookers endlessly tag themselves in photos, make status updates and accumulate vast numbers of virtual friends. Who does that remind you of?
Facebook's fake friends
Friends are fabulous – real friends, that is. Fiendishly gathering Facebook 'friends' to enhance a social networking profile is a hollow practice. Why the need to pretend to have armies of 'friends'? Who's to impress? What's to gain? How shallow a practice is this?
Facebook is a passing phase
Facebook is just a phase. And why would you spend your life devoted to a phase, unless that phase is parachute pants and you're MC Hammer? It too shall pass, the same way Tamagotchis and hula hoops did. Any day now, Facebook will be consigned to the dumping ground where out-of-date social-network sites go to die. In that virtual graveyard it will keep company with a sad and dejected Bebo, only to discover –in my dream anyway – that Twitter got there before it.
Facebook is more limiting than enriching
I swear, there is nothing about Facebook that could enrich my life. Many of my friends have left the site, saying the obsession is not worth the measly returns.
They weren't joking. In one study, 25pc of Americans surveyed said they missed out on an important life event while attempting to capture it for social media. In another, 57pc of those polled said they had more conversations online than they do in real life. Whether that statistic includes the conversations some people have with themselves, I don't know.
Either way, it gets worse. According to a Travelodge survey, 72pc of British people polled admitted to checking Facebook in bed. It's hard to know whether this tells us more about the nocturnal activities of those polled or the sleep-inducing qualities of Travelodge beds. Either way, the trend smacks of obsession in all its unhealthy, inappropriate glory.
Facebook is no forum for the reserved
It's not so much Facebook's somewhat casual regard for privacy that repels me, it's more the fact that there's nothing I want to share online. Then there's the fact that if I had to choose a forum for intimate discussion, I'd choose a soapbox on Grafton Street faster than I'd choose Facebook.
Facebook bores me
The concept of Facebook bores me no end. Honest, it does. Log in and you're hit with a wall of advertisements cannily chosen to appeal to your virtual self. Avert your gaze and you're left with – well, you're left with a sinking feeling as your senses are assailed by one post less interesting than the one before it.
I swear, if you think about Facebook, it's completely bizarre. This is, after all, a forum where perfect strangers accept invitations from perfect strangers to become 'friends'. So labelled, the friendship parody begins, with the most intimate details being shouted out lest anyone might care to listen. Most would avoid shows of such swaggering social imbecility in normal circumstances, but there is nary a normal thing about Facebook, which plays by its own rules.
Facebook is fickle and shallow
Facebook facilitates obsession with self-image and shallow friendship. It causes some to feel uncomfortable with their lives and others to embellish their realities. But don't take my word for it.
Research shows that one-in-four females distorts the truth about their activities when posting on the site. They do this to make their lives look more exciting. In the process, they contemplate the inadequacies of their existence and pine for what they've lost or what they never found.
While you'd imagine, given its popularity, that Facebook would engender a feel-good mood in its users, German scientists assure us that on visiting the site, one in three feels jealous and envious (whether this figure is higher in nations of begrudgers is anyone's guess, but I imagine it is).
While real friends won't go into a tailspin on hearing of your good fortune, cyber competitors might. And before you take solace in the fact that two out of three Facebook 'friends' don't admit to feeling miserable on seeing your happy postings, there's no room for complacency: they could be plotting to take you down with one gloriously pre-meditated click of the 'unfriend' button.
Big names who opted out
Malia and Sasha Obama
Julia O'Reilly (16) is a Transition Year student at St Joseph of Cluny Secondary School in Killiney, Co Dublin. She hopes to work in fashion and journalism when she leaves college.