Sonya Moriarty was once a successful actress, but lately the erstwhile darling of the London stage finds that the real-life role she covets — that of a person who can say no to a drink — is beyond her reach. "How much easier it is to inhabit someone else," she says.

The protagonist of "Bright Burning Things," Irish writer Lisa Harding's incisive novel, Sonya is intelligent and talented, mercurial and exasperating. She's an affectionate but impulsive single mother. A sanctimonious crank. A charismatic artist. And a woman who, on the cusp of middle age, is battling numerous demons.

Harding's plot is straightforward. Sonya, who drinks oceans of wine, is desperate to pull herself together, lest she lose her 4-year-old son Tommy.

Sonya's days are shaped by binges, hangovers and not-unjustified defensiveness. When she briefly loses track of Tommy at a beach, a haughty stranger questions her parenting skills. Returning home, a nosy neighbor asks why Sonya won't let Tommy drink milk. She replies with an animal-cruelty rant: "Disgusting ... The calves cry themselves hoarse."

Sonya may be an uncompromising vegan, but otherwise she doesn't have much impulse control. She embarrasses Tommy in public, then, at home, marinates herself in white wine. When she passes out, Tommy is left to look after himself — a frightening scenario given his fascination with fire.

Her drinking is self-medication for what might be mental illness. She hears "voices" and courts danger, driving recklessly and rushing into romantic relationships. Concerned for Tommy's well-being, Sonya's father forces her into rehab, telling her that if she doesn't go, the authorities will take Tommy. Can she make sobriety stick?

In tackling this question, Harding insightfully considers the burdens we place on single parents and people battling addiction. Addiction is an illness, but it's hard to think of another malady for which people who fail to heal are threatened and shamed. As for Sonya's public outbursts, they're unfortunate yet at least sometimes forgivable, frequently incited by people who malign her parenting abilities — and by extension, her love for Tommy. As her experiences remind us, people who need help are often condemned and penalized.

Harding's portrayal of alcoholism's insidious self-rationalizations hits the mark, and she offers a not-often-heard perspective on well known recovery programs. Anyone who's ever attended such a meeting will recognize her depiction of the prevailing atmosphere, which encourages sharing but sometimes turns into a melodramatic, male-centric vanity pageant: "Who has the greatest scars and, above all, who has the greatest capacity for forgiveness and gratitude and acceptance?"

Despite her skepticism, Sonya sees that the meetings are invaluable for some, like an alcoholic friend whose drinking stems from a childhood in which he was never hugged. "When I heard him share this in a meeting," Sonya says, "it had truth all over it." Same goes for this book.

Kevin Canfield is a writer in New York City.

Bright Burning Things

By: Lisa Harding.

Publisher: HarperVia, 336 pages, $26.99.