“I just can’t believe it. That all you have to do is sleep with somebody and get caught and you never have to see your in-laws again. Ever. Pfffft! Gone. It’s the nearest thing to magic I have yet found.” That’s the Anne Enright voice all right – wry, disabused, reckless, candid, funny. The hardened, suffering speakers in her recent fine story collection, Taking Pictures, use this tone; the grim damage of her Booker-winning The Gathering is energised by all that darkly comic unflinchingness.

The Forgotten Waltz, as its romantic title suggests, has more of a soft centre than she usually allows herself. Each chapter is headed by the title of a tear-jerking pop song (“Will You Love Me Tomorrow”; “Stop! In the Name of Love”; “Save the Last Dance For Me”), and the woman who tells the story has to keep telling us how deeply in love she is: “This is what puts me beyond regret – the sweetness of my want for him, the sense of something unutterable at the heart of it.” “By Mullingar I thought, if I did not see him soon again, that I would surely die.” “We want to hold on to the knowledge that comes when we look into each other’s eyes.” “I love him. And that is as much as any of us can know.”

However, the context, and the object, of this sentimental intensity, is as unromantic as you can imagine. We’re worlds and generations away from the risky, convention-defying sexual adventures of Edna O’Brien ’s isolated girls, the violent repressions of country people in a McGahern story, or the quiet, hopeless longing of William Trevor ’s small-town lovers. This is Ireland in the late 2000s, and Enright’s people in this novel are consumers and communicators, businesswomen, property owners, Dublin suburbanites. They work in IT and consultancy and have beach houses and barbecues, they go wind-surfing and hold parties for “a guy who was taking a year out to be with his yacht”. They host New Year’s Day brunches in Issey Miyake pleats, their solicitors wear Alexander McQueen shoes, their love-affairs are kept going through texts and meetings in airport hotels and presents of Hermès scarves. They measure out their lives in large glasses of imported wine: there’s the phase of being “mad into chardonnay”, the “sauvignon blanc” years of happy marriage, alsace riesling as a spur to adultery, cracking open a “Loire white” as a reaction to bereavement.

Even the narrator, Gina Moynihan, who stands edge-on to this world, and derides her status-conscious sister for minding that the woman three doors down at Brittas Bay has wooden blinds on her mobile-home windows, nourishes her own “Sunday-supplement dreams”. She belongs to a boom-town that defines itself in terms of property, “when if you wanted your kitchen tiled (and we wanted little else), you had to fly the workman in from England, and put him up in a hotel”. The cost of adultery is not in shame or guilt, as it might once have been in Ireland, but in house-sales. “Who would have thought love could be so expensive? ... The price of this house plus the price of that house, divided by two ... Thousands. Every time I touch him.”

The story is, almost, an ordinary one. A 34-year-old married woman – sexy, energetic and independent-minded – falls in love with an attractive married man she meets at her sister’s house. He has a daughter, who seems a bit odd. The affair goes through all the predictable stages: a drunken one-night seduction in a foreign hotel, a clandestine office romance, discovery and family recriminations, the romantic affair turning into a bickering second marriage, the ultimate loneliness of the woman. As always, Enright is good at that, as she is at sexual desire, the “copulatory crackle in the air” between the two lovers. And she turns a sharp eye, and ear, on the cliches of illicit love (”We don’t really know each other”) and of marital accusations: “You never. I always. The thing about you is.” The lover turns out to be a serial adulterer and not much of a person, after all, and that blank at the centre makes this a thinner book than The Pleasure of Eliza Lynch or The Gathering.

But what deepens the mix are two discomforting, awkward and delicately handled factors. One is the sudden death of the sisters’ dashing, stylish and gallant mother, who in the face of adversity would “get out the powder and blush” and spray on some Givenchy. Because of her consuming affair, Gina has not paid attention to her mother’s illness, and the death catches her by surprise. Parental losses – as, over and over again, in Taking Pictures – are things that Enright understands, and in The Forgotten Waltz this grief is more touching than the grief of desire. The other fine thing is the difficult, insistent presence of Evie, the lover’s daughter. First seen as an overweight, overwrought little girl, she grows up and makes more claims on our attention as the novel goes on. We learn her painful story, which changes our view of everyone else in the book, and Gina has to learn how to deal with her. That impossibly difficult yet involving relationship, between the father’s mistress and the angry adolescent girl, gives us the last – and one of the best – scenes in the book.

The novel is told in retrospect from the end-point of the snow-bound winter of 2009, when Dublin has ground to a halt and the streets are empty and blanketed, as if in a faint tribute to the end of Joyce’s great story of love, loss, family and nation, “The Dead”: “snow was general all over Ireland”. This Ireland of the 2000s is dead, too: the bubble has burst, the boom is over, all the buying has stopped. “We listen to it ... the rumour of money withering out of the walls and floors and out of the granite kitchen countertops, turning them back to bricks and rubbles and stone.” Gina tells her lover, of their affair, that “the whole project is about failure. It has failure built in.” The parallels between different forms of expensive wastage are not laboured, but are made plain.