Why does the short story lend itself so naturally to the muted but still shattering sentiments of yearning, nostalgia and regret? How many William Trevor tales focus on the moment when a heart is broken or at least badly chipped? Though Mavis Gallant’s work bristles with barbed wit and trenchant social observation, her most moving stories often pivot on romantic ruptures and repressed attraction.

Obviously, there are exceptions to be found amid the carnage of Isaac Babel and Tim O’Brien, the waking nightmares of Kafka, in Flannery O’Connor’s knock-down, drag-out struggles between God and the Devil. But in its search for the surprising yet inevitable chain of events that will illuminate a character’s - and the reader’s - life, a short story has the power to summon, like a genie from a bottle, the ghost of lost happiness and missed chances. That’s partly why this kind of fiction can affect us as intensely as a novel. Arguably, our final vision of Joyce’s Gabriel Conroy, at the end of “The Dead,” gazing at the snow and feeling his soul swoon slowly over the graveyards of Ireland, packs the emotional wallop of Captain Ahab’s battle with Moby Dick.

As its title suggests, there’s melancholy to spare in Colm Toibin’s new story collection, The Empty Family. Toibin, whose novels include The Blackwater Lightship, The Master and Brooklyn, doesn’t shy away from the hard stuff: the deaths of parents, the end of love, the point in life at which a person begins to suspect that everything interesting and exciting has already happened. Retrospect is a major player in these dramas; regret makes its entrance onstage, and a character relives the sort of experience recalled for the obvious reason that it was so painful.

The opening story, “Silence,” based on an incident Henry James recorded in his journal, centers on Lady Gregory, the Irish poet and playwright. Seated next to James at a dinner, knowing the Master enjoys being entertained with anecdotes he can draw upon in his work, Lady Gregory creates a fiction of her own by offering a heavily embroidered version of a long-ago love affair over which she still suffers. In “One Minus One,” a monologue addressed to a former lover, the narrator recalls a time when he was plucked from his promising new life in Manhattan to return to his old life in Ireland, where his mother was dying.

For Toibin, memory seems not merely a function of the heart but proof that the heart exists. Even the least appealing of these mostly sympathetic characters is humanized or humbled by an immersion in the past. So, in “Two Women,” an imperious set designer returns from Los Angeles to Dublin, where a stranger’s resemblance to the only man she truly loved topples her off her brittle perch, and she spirals back into her dead lover’s orbit.

Like the Dubliners who populate Joyce’s fiction, many of the people we encounter in these pages can’t escape the fierce, damaging winds gusting from their homeland. Revisiting their birthplace, they experience the pleasures of return, the shock of seeing how poorly reality compares with what they remember, along with a prickly awareness of all the reasons they left. For Paul, the protagonist of “The Color of Shadows,” this discomfort is sharpened by the inability of his Irish Catholic family to accept the fact that he is gay. In “The New Spain,” a woman goes back to her native Barcelona (where several stories are set) soon after the fall of Franco. There she discovers that the distance between her and her family, a chasm that originated in her Communist activism during the dictatorship, has been widened by domestic events that have transpired in her absence: her grandmother’s death, a quarrel over a legacy. Meanwhile, the political ideals that once inspired her succumb with hardly a fight to the seduction of having inherited a parcel of beachfront property.

The most affecting stories in “The Empty Family” are the longest and most complex, stories in which Toibin allows the accretion of incident and detail to engage us most fully in the fates of his characters. The novella-length finale, “The Street,” is a sensitive account of a romance that blossoms, despite daunting obstacles, between two men newly arrived from Pakistan, living in the claustrophobic and oppressive immigrant community of Barcelona. It’s to Toibin’s credit that after the story ends, the reader continues to wonder about the future of this brave couple.

Perhaps the best story in the collection, “The Pearl Fishers,” is told in the voice of an author of “grim, almost plotless thrillers with gay subplots” and “overwrought and graphically violent screenplays.” Our hero is invited - summoned, really - to have dinner with a married couple, a man named Donnacha and a woman named Grainne, both of whom he has known since they were at school together decades earlier. The two boys (as they were then) were lovers before Donnacha linked up with the fiery, strong-willed Grainne, a religious reformer who has gained some notoriety by insisting “that she and other like-minded lay people represented the true Catholic Church more than the bishops and priests.”

Over their meal at a Dublin hotel, Grainne declares, cryptically, that it is time for the truth to be revealed. But even as the narrator prepares himself to be confronted with his youthful affair with Donnacha - a relationship of which Grainne has apparently been unaware - he discovers that the secret she has in mind is more troubling than the heartbreak he has concealed.

Interspersed with passages that return us to their younger days, the threesome’s conversation is richly layered with subtext, and the portrait of Donnacha, at once passive and charismatic, is the most nuanced in the book. In “The Pearl Fishers,” multiple ironies, some obvious and others quite subtle, are allowed to shimmer lightly in the atmosphere surrounding the former friends. Resonating throughout the story, the contrasts between action and intention, expectation and outcome alter our perception of the characters: of who they were as teenagers and how they became the adults on whom we are eavesdropping.

At the story’s conclusion, the narrator imagines his friends returning to “lamplight, shadows, soft voices, clothes put away, the low sound of late news on the radio.” Crossing Dublin, he tells himself that “no matter how grim the city I walked through was, how cavernous my attic rooms, how long and solitary the night to come, I would not exchange any of it for the easy rituals of mutuality and closeness that Grainne and Donnacha were performing now. I checked my pockets to make sure I had my keys with me and almost smiled to myself at the bare thought that I had not forgotten them.”

This resigned and touchingly hollow attempt at self-consolation seems emblematic of what so many of the characters in “The Empty Family” want or are willing to settle for: a place to call home and the comfort of having remembered the keys.