The unheralded martyrdom of the novelist! To understand Cusk and her relationship with criticism requires little in the way of literary detective work. She is one of those writers invested in her own mythology, and often truthful about her motivations. For Cusk, a writer is someone trapped in childhood, trying to see its truth. In her essay collection, “Coventry” (2019), she describes being punished for her outspokenness by her parents, who would stop speaking to her. She was sent to boarding school, which she seemed to interpret as exile. Banishment and silencing are her great themes and patterns.

From the start, even her admirers could not deny her “mix of scorn and compassion,” as Hilary Mantel put it. Cusk’s work has been repeatedly criticized for its snobbery and insistent, almost obsessive cruelty about other people’s appearances, and fat and fleshy bodies specifically. Her memoirs — “A Life’s Work” (2001) and “Aftermath” (2012) — now regarded as feminist texts and praised for their honesty, had her branded as a sadist and narcissist; she was pilloried for admitting to the loneliness and difficulty of early motherhood, for exposing the private lives of her children, for being unfair to her ex-husband. “My mode of autobiography had come to an end,” she said in a 2014 interview with The Guardian. “I could not do it without being misunderstood and making people angry.”

She performed a vanishing act of sorts, returning with an entirely new style in her influential “Outline” trilogy, writing from an “annihilated perspective,” through a narrator who seems to passively collect and report other people’s stories. “‘Outline’ is the essentially defensive position of saying, Well, you can’t hurt me, because I don’t exist anymore,” Cusk said. The novels were praised for their innovation, for forging a form of storytelling without the contrivance of traditional character and plot. The novels were darkly funny, too, full of caricatures of other well-known novelists — reportedly Jonathan Franzen, Karl Ove Knausgaard, Damian Barr — gassing away with self-importance.

In comparison, “Life of M” is a lost little book — undisciplined, unfocused and instantly forgettable. The New Yorker deemed it Cusk’s “weakest novel.” The true faults with the book turn out to be less ethical than technical. Cusk may have jettisoned the conventional narrative lumber of character and scene, but she replaced them with a series of pieties and poses all her own that, with time, have started to feel strained, the characters who sound the same and speak in portentous tones about fate and chance, the fetishistic descriptions of interiors, the inexplicable shifts in point of view.

Stripped of the scandal, the book has little life of its own. It will fade. But some of the questions it raises about harm ought to linger. Cusk’s champions insist “Life of M” isn’t cruel or exploitative but an exploration of cruelty, an invitation to consider, in complicated ways, the nature of exploitation. In this view, it is not Cusk but the callow reader who is guilty of harm by projecting upon Portman her own feelings of affront, who is too stupid to see that it is not Cusk but the narrator who is responsible for this cruel portrait. To the critic Molly Young, “It seems impossible that a person of functional literacy could take ‘The Life of M’ as an act of Cusk-on-Portman violence.”