At a screening several weeks ago of Richard Linklater’s “Boyhood,” a rambling chronicle of Texas childhood and the way adults grow into parents, I sat with New York Times columnist Ross Douthat. The movie focuses on Olivia (Patricia Arquette), who is raising her two children, Samantha (Lorelei Linklater) and Mason (Ellar Coltrane), with only intermittent help from their father, Mason Sr. (Ethan Hawke), subject matter that sparked some friendly banter between us about whether “Boyhood” is a case study in family breakdown or proof that marriage promotion is a failure.

Director Richard Linklater and actress Patricia Arquette attend the Brussels premiere of “Boyhood” on June 21. (Mark Renders/Getty Images)

“Boyhood” is, of course, vastly more than a policy brief: It is a stunning act of temporal filmmaking, a testament to just how awkward the pop culture of the aughts has been and an antidote to the artificially high stakes that characterize so much pop culture. But Arquette’s remarkably humane performance is evidence of just how difficult it is to extrapolate personal advice from policy research and how inadequate those proscriptions can feel up against actual experience.

Olivia is a good mother, if under pressures that strain her patience. She reads “Harry Potter” books to Mason and Samantha in bed, prioritizes spending time with her children over going out with a boyfriend who seems to wish Olivia could be unburdened of her status as a parent and talks frankly with her kids about their financial situation and her reasons for going back to college.

Olivia also does everything marriage promotion advocates would have her do, except stay with Mason Sr. The reasons for their breakup are left unclear: Olivia suggests that it was not healthy for the relationship to continue, while Mason Sr. tells his children that a reunion is not his call.

Olivia goes back to college, where she meets and eventually marries one of her psychology professors, Bill (Marco Perella). Initially, Bill seems like a generous partner and a disciplinarian who can balance the influence of Mason Sr.

But the promise of the new family curdles. Bill turns out to be an alcoholic, who makes the flimsy excuse that “This is just in case we have guests this weekend” when he buys liquor. “He always says that, but we never have guests,” Mason’s stepbrother Randy (Andrew Villareal) tells Mason.

He is also a petty, nasty man who has Mason’s head shaved when he decides the boy’s hair has gotten too long. The fury in Coltrane’s eyes as the barber takes shears to his head, and the wound in them the morning after when he tries to get out of going to school rather than expose his shorn head to his classmates, are small marvels of acting.

Bill’s cruelty eventually becomes violent. One day when Mason and Randy come home from a bike ride, they find Olivia, face-down and weeping, on the floor in the garage. “Your mother had a little accident. Now she’s being dramatic,” Bill tells the boys. It is a terrible come-down from Olivia’s optimism when she and Bill returned from their honeymoon in Paris, or even from the feeble promise she holds out to Mason after the disastrous haircut that “now we have a family.”

After Olivia and the children flee Bill’s house and go to stay with a friend, Olivia makes a tortured attempt to reassure Samantha that they and their stepsibilings will be safe. The abstract idea that Olivia and her children would be better off if she were married has foundered. And Olivia is just one woman up against her own near-poverty and her lack of legal guardianship of her stepchildren. Her vulnerability is terrible to witness, more so for its display in front of her daughter.

It is a testament to Olivia’s persistence and courage that she continues both with her education and her attempts to find good influences for her children, finding a job as a professor in San Marcos and settling in with Jim (Brad Hawkins), one of her students and a veteran of Iraq.

Where Bill combusted under the weight of his own self-loathing drunkenness, Jim, who was once idealistic about what he could achieve as a soldier, seems to be weighed down by the reality of a corrections job in Texas. He starts out as the sort of optimist who buys a foreclosure with Olivia and sets about renovating it. When a 15-year-old Mason comes home after curfew, Jim asks whether the boy knows what time it is, then turns an opportunity for chastisement into a chance to wish the boy a happy birthday.

Several years later, he is reduced to drinking beer on the porch and berating Mason, a slack but not unkind teenager, for his thoughtlessness. “You know, Jim? You’re not my dad,” Mason tells him, hurling the oldest insult known to stepchildkind. “You know how I know that?” Jim spits back at him. “I’m actually here.” It is not enough. Jim vanishes from the movie, and the house follows close behind him.

“I really enjoy making poor life decisions keeping us on the brink of poverty,” Olivia tells Mason in exasperation toward the end of “Boyhood,” worn down by her divorces and the false promise of home ownership, as well as her emptying nest. She is being harder on herself than the movie is, or indeed I think most policymakers of any stripe would be. Olivia has forged a fulfilling, successful career after early setbacks and raised two college-bound children in trying circumstances.

“I knew this day was coming. I just didn’t realize you’d be so f—ing happy to be leaving,” Olivia tells Mason in tears as he prepares to leave for college. “I just thought there would be more.” The tragedy for Olivia at the end of the film is not that she has failed to produce the sorts of outcomes that marriage is supposed to facilitate, but that she feels so sad about her success.