Kirsten Dunst was losing it, and Hollywood was starting to worry. During production of 2008's "How to Lose Friends & Alienate People," she and her boyfriend broke up, and director Robert Weide saw "a girl who was just right on the edge, emotionally feeling wiped out and devastated."

Perhaps it was inevitable. After all, she'd been acting for more than two decades — and was only in her mid-twenties. She had started performing in commercials when she was 4. Her earnings were set aside for college, but she never went — those plans were derailed when, at 12, her career took off after aGolden Globe-nominated turn opposite Brad Pitt in "Interview With the Vampire."

She went on to become Mary Jane Watson in three Spider-Man films that took in more than $2.5 billion at the box office worldwide. But aside from that, the quintessential girl-next-door seemed to be floundering. Tabloids presented her as an out-of-control party girl, publishing photos of her bleary-eyed and bra-less, while blogger Perez Hilton labeled her "KiKi Drunkst." Her career wasn't faring much better: She had appeared in several flops, like the Cameron Crowe romanticcomedy "Elizabethtown," and Sofia Coppola's retelling of "Marie Antoinette."

Feeling what Weide described as "the weight of it all," Dunst checked into Cirque Lodge, a drug and alcohol addictiontreatment facility in Sundance, Utah, citing depression.

She even considered quitting acting.

"I think I just came to a point in my life where you just have to stop," said Dunst, eating breakfast for lunch on a fall afternoon at a Silver Lake coffee joint filled with willowy artist types. "I had to reevaluate getting older in my twenties — and just questioning how I was living as an actress — why I did it. I just needed to take a break and figure out what makes me happy… how I could re-direct my career in a way where it was more for me."

After her six-week stint in Utah, a move from L.A. to New York, and more than two years off the big screen, the actress, now 28, is cautiously returning to movie stardom, starring opposite Ryan Goslingin "All Good Things." In the film, based on the life of Manhattan real estate scion Robert Durst, the two play a married couple whose initially idyllic romance becomes increasingly troubled and ends with the wife's disappearance (and suspected murder).

Dunst said the intimate production was a welcome change from the world of Spidey stunts and big-budget studio sets.

"It's just a more freeing medium when you don't have the time to sit in your trailer for hours because they're setting up the special effects shot and then you better be crying in 15 minutes," she said, taking continual drags on her cigarette. "That's working on 'Spider-Man.' "

But it was Dunst's performance as Mary Jane that caught the attention of "All Good Things" director Andrew Jarecki.

"Even in really commercial films, I think she always provides the heart of the film," said Jarecki. "In'Spider-Man,' it's hard to really care about somebody in the context of a cartoon unless the person that you're watching is very real and has natural quality."

Dunst began production on "All Good Things" shortly after her spell in Utah. Jarecki said that when she arrived in New York for an eight-week rehearsal period, she was focused.

"She's extremely methodical and organized. She's got that German blood — there is no part of her that is trying to skate by," Jarecki said. "She's very adult. She sort of has been, in some ways, even the center of her own family for many years."

The actress grew up in the San Fernando Valley, where she lived with her mother, a former employee of Lufthansa Airlines. She moved out and bought her first home at 22, but quickly began feeling isolated. She said she felt like everyone surrounding her either worked in or couldn't stop talking about the entertainment business.

Weide, who first met Dunst as a Barbie-doll-loving 13-year-old when they worked on a film together called "Mother Night," said the pressure of an accelerated adolescence is what caused her to break down.

"She had been doing this since she was a kid, and she had no complaints about it — but said it technically wasn't a choice she had made, it was something that had happened to her. To a great degree, she had a lot of adult responsibilities on her shoulders from an early age," said the filmmaker.

If Dunst seems relaxed about her move back into acting, she is still working out how much to say about her hiatus.

She's open about her decision to move to New York, buying and redecorating an apartment, taking art classes, and pausing to think about her career choices.

"I was just done living in L.A. There comes a point when you don't want to have your hair or makeup done. I wanted to do things that I could be creative in, anonymously," she said, bobbing her straw in and out of her iced coffee. "And wait for a project that I thought I could really do something with, you know? There's a lot of roles for girls in their twenties, and it's harder to find roles where the girl isn't just, like, cute and the love interest and nothing happens to her. And this film, you could be messy and do a lot of things."

Yet asked how time in rehab affected her and changed her thought process, Dunst shut down. "I feel like I've said enough about that," she said, bristling.

Dunst has already earned positive reviews for her performance in "All Good Things," which was released via video-on-demand in early November and hits theaters in Los Angeles this weekend. She has been promoting the film almost entirely on her own for the last month, while co-star Gosling has been touting his upcoming romantic drama "Blue Valentine."

Asked in an interview in which he promoted that film if he was proud of his work in the Jarecki movie, he paused, saying only: "Yeah, I'm really proud of what Kirsten does in the film. I think she's great. It's great to get to be a part of that."

Nowadays, things seem less volatile for Dunst. She says she's OK with the fact that she won't be a part of the fourth "Spider-Man" film, which Sony has decided to re-boot without its original cast. She's about to start filming a role in the screen version of "On the Road," and next year she'll star in a Lars Von Trier film, "Melancholia." She also is in a seemingly steady relationship with Jason Boesel, drummer for the band Rilo Kiley.

Watching cars pass by as she sat at the sidewalk café, Dunst said she feels like she's in a good place.

"I really trust my gut more than ever," she said. "I just know what's right for me. I won't just take a movie to work. Before, I think I wanted to work because I wanted to stay busy. But I don't mind waiting."

amy.kaufman@latimes.com