Mobile messages: cheating by text

Would I be on the brink of having an affair if it weren't for the sleek little apparatus that I transfer from pocket to pocket? I really don't think so. Sure, I've seen The Ice Storm, read my Updike; people cheated on each other before they could slip almost instantaneous messages – and pictures – to one another all day and night, but I don't know how they managed. My afternoons are not lazy with opportunity, my evenings are not filled with cocktail parties that drag on, long and smoke-filled into the kind of flirtation caused by too many drinks and too few appetizers. Maybe the mobile phone is the new martini, the key party of the moment.

Now, the man I want to sleep with and I can both be home, with our children safe in their beds, watching movies on our respective couches with our respective spouses snuggled up beside us, while we wait for that slight vibration against our skin, that sexy electronic zing, that signals a new email. It sits there waiting until the spouse gets up for another glass of wine, or to use the bathroom, whereupon we slide out the phone with eager fingers and devour the missive: pithy, suggestive, tantalizing. Then, despite our best intentions to wait an hour, a day, forever, to respond, we find a way to sneak off for just a moment and fire back the perfect, crafted little retort.

This flirtation might never have occurred, and certainly would not have escalated as rapidly as it did, without the existence of email, and particularly my smart phone, which makes checking it compulsively easy. I suppose it's possible to banter coyly on the sidelines of the football field or during a rare adults-only party, but in my circle of obsessively good parents there is no soft slide into debauchery. Drinks are limited to two, drugs are nonexistent and marriages are seemingly solid and staid. All the sordid impulses get pushed online, where the anonymity of email gives you the courage to write something shocking, with bravado unimaginable face to face. And when you add in the convenience of that slim little rectangle, with its near-instant gratification, things can ramp up pretty fast.

I met the object of my desire when our older children started nursery together. Our children sat next to each other and became friends, and at our first all-school gathering, I remember scrambling desperately for a pen to get his number and schedule a play date. My interest was purely maternal, but emotions began to shift. At a birthday party, I hugged him hello and suddenly found myself thinking about sex.

The crush lingered for a while; he seemed content in his marriage. He was an attentive father, an excellent baker, his house was a spotless mid-century modern – whatever I thought I spied in his amused eyes must have been my imagination. But the day he and his family came to my oldest child's birthday party, I felt his eyes on me. That night I dreamed of standing before him and longing for him to kiss me with an intensity I hadn't felt in years. I found an excuse to email him: a small jacket lying lonely in the living room. Perhaps it was theirs? I wanted to end the note with a question. I wanted him to get back to me.

He emailed promptly. The jacket wasn't his child's. But perhaps I'd like to meet for coffee? Our hands barely grazed each other that day, but online, the notes grew friendlier and, eventually, hungrier, each message a small piece of kindling thrown on the fire. That was less than a month ago, and here we are on this precipice; cheaters in text, if not yet in deed.

I should point out that there's nothing wrong with my marriage. Nothing, other than the fact that it's 10 years old. My husband is handsome, supportive, loves his children immensely, and our sex, on the relatively rare occasions we have it, is great. But most nights he works, and I fall asleep on the couch, and the thrill of the unfamiliar is electric. (It's my husband who's the unexpected beneficiary, although he would regret the day he bought me my phone if he knew the reason for my sudden friskiness.) I suppose I thought nearly 10 years of pregnancy, nursing, waking up in the middle of the night, being endlessly patient, remembering permission slips, managing school parties had turned me into a good person, the kind who didn't do these things. But now that the children are older and need me less, I realise maybe it wasn't morality that kept me in check all those years; maybe it was sheer exhaustion.

Now I feel eager and itchy all day long. I swing back and forth between hoping our connection will fizzle out, and being terrified of losing the euphoria I feel. I tried to go cold turkey the other afternoon, spending the rainy day alone in the house with my two-year-old, but I found myself at 4.30 with a beer in the kitchen firing off a desperate message to him: "Jesus Christ, what have you done to me? I think I'm having withdrawals!" My finger hesitated before tapping the send key, and almost immediately afterward I wanted to take it back. But when the phone vibrated knowingly on the kitchen counter I nearly wept with relief, and snatched it up, allowing the potatoes I was supposed to be stirring constantly to scorch. I danced around the kitchen after I read the message, then gave up entirely on trying to remember how to reassemble the Cuisinart.

I have begun to sleep with the phone on the bedside table at nights, listening, even as I sleep, for the noise of an incoming message. When I hear that insinuating sound, it wakes me, and I sleepily check it, usually to be disappointed by a mass-message from Toys R Us announcing its latest discounts. I am constantly hopping back and forth from my different mailboxes, from laptop to phone, making sure I have deleted everything incriminating. Just one innocent-looking message could unravel into mayhem, trailing, as it does the whole illicit conversation.

Lately, we've pushed it one step further, into dirty pictures territory. We all know that teenagers are sexting, but as it turns out, so are adults. Before I was caught up in my own ill-advised dalliance, I regularly excoriated a friend of mine to my husband, because she and her flirtation – an old high-school boyfriend, rediscovered, naturally, on Facebook – were sending a stream of risque images from coast to coast. Then, the other night, I was sitting on the couch across from my husband and I flipped open my computer to check my email. What I saw sent my fingers scrambling for the delete button and me upstairs with a stiff drink. Even a grown man, an excellent father, is not immune to the temptation and ease of the camera. The look on his face the next morning, at preschool drop-off, was beautiful.

Our mobiles can only take us so far. As the stakes get higher, our messages have gotten cooler, more pragmatic. I don't know how long we can keep this going, or what happens next. Maybe it's only the beginning. Or maybe we've had all we need.

The author's name has been changed