Kate Winslet took on the mother load in ‘Mildred Pierce’

Rarely is a scene as heartbreaking and hard-earned as the final one in HBO’s “Mildred Pierce,” when Mildred’s ex-husband pushes her to finally detach from Veda, the gifted daughter who has given her so much grief. “To hell with her,” Bert coaches gruffly, pointing Kate Winslet’s Mildred down the only path to her emotional survival. “All right, Bert,” she manages through her tears. “To hell with her.”

Many months later, Winslet says she is finally able to get some perspective on the process that went into her performance, one of the most talked-about elements of a production that was exceptional on many counts.

“Being told to cut off and walk away from a child — I cannot imagine it. I think I’d rather die,” says the U.K. native, who’s a mother of two. “But it was clear at that point that for Mildred to go on living, she needed to be free of that anger and that hurt.”

HBO’s five-part miniseries, closely based on the Depression-era James M. Cain novel, is about many things — Mildred’s struggle to survive in tough economic times; her entanglements with men; her eventual triumph in business. But more than anything, it’s about her obsessive, even unnatural attachment to Veda (Evan Rachel Wood) — a love that finally costs her everything she has.

Winslet, speaking by phone from her home in New York, where she’s taking a break after shooting the film version of Yasmina Reza’s play “God of Carnage” in Paris, tries to shed some light on that relationship.

“Mildred is full of holes; there are empty pockets in her own spirit that she hasn’t nurtured, and has only filled with love for her child,” she says. “As Veda slips away and becomes more and more unknowable, she’s naturally trying to hang on to her, but I think it’s for reasons more to do with Mildred.”

So grounded and sympathetic is Winslet’s portrayal (she says she never watched Joan Crawford’s Oscar-winning turn in the 1945 feature film) that it’s hard to view her Mildred as less than whole. But an unhealthier side of the character comes to light in the series’ melodramatic last chapter, after Veda’s machinations push Mildred to the edge of madness.

In one scene, she kisses her lovely daughter full on the lips while she sleeps. In another, after a stunning betrayal, she nearly strangles her.

“I’ve had people ask me, ‘Was it a sexual love?’” says Winslet. “And I’ve said, [she gasps] ‘What do you mean?’ I never saw it as that.” Winslet said the kiss occurred on the spot — Mildred was kissing her sleeping daughter on the forehead when director Todd Haynes encouraged her to take it a step further. “He said, ‘Why don’t you just go ahead and kiss her on the lips?’ So I turned to Evan and said, ‘I’m sorry, babe, do you mind?’ It wasn’t an epic part of the story line.”

But later, when Veda is discovered in bed with Mildred’s new husband, Monty Beragon (Guy Pearce), and she displays a brazen — even inhuman — lack of shame or remorse, Mildred violently attacks her. “She wanted to kill her,” says Winslet. “And had Monty not swooped in and un-clawed Mildred’s fingers from Veda’s throat, I’ve no doubt that she would have.”

“My God, it’s almost unimaginable how devastating that would be,” she says of the double betrayal and what it cost her to portray it. “We just felt sick, all of us. But that’s acting. And we were all in it together.”

“It’s a good thing we’re speaking about this now, and not when we were shooting, because at the time I wouldn’t have been able to speak, I would have just —” she trails off into a croaking sound. “Everything about who I was in relationship to Mildred was happening on the spot, as we were shooting.

“What I’ve learned about acting,” she continues, “is that it needs to be mysterious. If you overthink how a beat needs to be played, it can trip you up. Because you’re trying to do something that is real and sincere in the moment, so that people believe you. There are times when you just have to put yourself as deeply and firmly in a character’s shoes as you can.”

For her costars, Winslet’s feat in anchoring the five-hour drama — she appears in nearly every scene — is all the more remarkable given that she was in the midst of her own divorce, from director Sam Mendes (“Revolutionary Road”), her son’s father.

“Her intelligence and capacity to do this detailed and complex role while dealing with her personal life was just mind-blowing,” says Pearce. “We all knew she was going through a breakup, and yet she was so present, and so prepared. And furthermore, she’s funny, and forever entertaining to be around. She’s a real leveler — to her, everyone in the room is equal. She’s the bee’s knees, really.”

For Haynes, Winslet’s willingness to explore Mildred’s weaknesses was essential. “Kate and I both love characters who challenge your sympathies,” he says. “To make Mildred more culpable, more mixed up in the complex pathologies of motherhood, which here get taken to extremes — that made the project so much more interesting. To sustain something over five hours, we really needed to feel divided about Mildred at times.”

Even Winslet felt that conflict. She says: “At times, I just wanted to smack Mildred, and say, ‘What the …, woman, you’re powerful! Go be powerful, and stop letting this child drag you down!”

The project marked Winslet’s first significant small-screen role since her teens, when she appeared in a string of British TV series. “I’d absolutely to do it again,” she says. “But not for a while. It was absolutely all-consuming.”

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