this image is not available
Media Platforms Design Team

Jennifer Aniston's house, which she shares with her fiancé, Justin Theroux, is set high up on a sunny hill overlooking Los Angeles. It's large and compound-like, befitting a star of Aniston's shininess in the Hollywood orbit. But it is also, and very distinctly, a home. There are oversize cushions and throws on the slouchy couch, high-chic Jacques Adnet chairs ("they're the most comfortable chairs in the room!"), a Buddha you could high-five.

Aniston comes racing in from the kitchen, a jazzy blur in trim white jeans, a navy T-shirt, and taupe wedges. She loves this house, loves houses in general—renovating, doing them up, making a home. "It's what I love to do," she says. "It's a great outlet for me, a hobby, if you will." The next plan is to renovate Theroux's apartment in downtown Manhattan. "I've got to get my hands on something because I can't sit still." She adds with a verbal wink,"I mean, I haven't done anything since June, for Chrissake."

While Aniston characterizes herself as having a "healthy amount of ambition," she says, "I don't live to work; I really do work to live. I love my home, I love my dogs, I love my friends, I love the simplicity of watching a sunset." She walks her three dogs, Dolly, Sophie, and Clyde around the property every morning. "There are moments when you have to stop and pinch yourself and go, 'I'm here,' " she adds. "I did something good."

So, yes, everybody, Jen is good. Jen is great, in fact. Read her a recent magazine headline titled YOU CAN STOP WORRYING ABOUT JENNIFER ANISTON NOW, and she responds drily, "Oh, thank God. Am I finally all right?"

The Narrative. You know the one. After a decade the narrative has finally gotten old. "I think people are starting to feel like, Are we that stupid?" she says. "It's like how many times can Deidre Hall die on Days of Our Lives and they bring her back to life? Eventually they're going to be like, 'Guys, she can't do that! She can't die and come back to life and now she's possessed.' Seriously. How many times can I be out there in the world, enjoying my life, and yet the narrative is 'Poor, Sorry, Sad in Love Jen' … whatever the stupid headline is."

The story that has taken its place is simple: Aniston, frankly, doesn't "give a shit." She pauses. "It's the detachment from it. There was a part of me that used to get very upset. I was guilty of getting too up in arms about stuff that wasn't real, phantom boxing with something that's not even there. Now I'd rather just focus on people and things that are here, happening, and what's yet to come. My friends, my family, wonderful people I work with. We know what the real is."

"Oh, thank god," She says drily. "Am I finally all right?"

Aniston's "real" is taking her to new places. She has just returned from the Toronto Film Festival, where her performance in the new drama Cake is the unequivocal best of her career, with the words "standing ovation" and "Oscar?" being bandied about. Of the role, where she plays a caustic woman suffering from chronic pain, she says: "It was the most challenging part I've ever done, and also one of the most rewarding and fulfilling. There was struggle involved." Aniston could very easily surf on rom-coms for the rest of her life. "Ha! That sounds like a terribly boring existence," she says. "I love doing comedies, though. It takes skill to bring that joy." OfCake, she observes, "You know, I don't know if I would have been able to do it five or 10 years ago. But I was ready to challenge myself."

The performance required that Aniston not only forgo makeup entirely but also have scars applied to her face, have greasy hair, and wear bulky clothes. "I remember the first day of shooting when I had to be outside, and it was not my most appealing look, it was kind of horrific. But I had this weird freedom. Now I'm like, 'Well, it doesn't get worse than that.' You have to not care, because I was starting to feel very isolated and trapped because I didn't want someone to get a stupid picture or whatever."

Personal security, of course, can breed a sense of adventure. "There is absolutely something to feeling so full and safe in life," she says. "It's been an amazing decade of really looking inward and exploring all of the avenues that exist inside. Sometimes they're fabulous and sometimes they're dark and sometimes they're confusing, and who knows? I think if you get to a certain point, you're ready to tap into something emotionally and put it out there. And it is very vulnerable, and it's a little scary, but what's the point if you don't give yourself a little boo every once in a while?"

Daniel Barnz, Cake's director, has said he wanted to work with Aniston "because we had to cast somebody who you can forgive immediately." After all, she could probably go punch someone in the face and people would just "get it." "Ah, there are some people I would punch," she says wryly. "I'd do that to a paparazzo probably."

However, Aniston is "a forgiving person," she says. "I absolutely am. I think it's extremely important to forgive. Otherwise it just builds up like toxic waste. There's nothing worse than holding a grudge. Listen, people can do unforgivable things, but you have to let it go and say, 'Look, we're all human beings. We make mistakes.' To hold any kind of resentment is like taking rat poison and waiting for the rat to die."

On Theroux: "He's one of the most humble, decent human beings. He's not an ass."

I'm having some Brie," Aniston says, jumping up and wrangling a dog off my lap. Talk turns to the movie business. Ask who her creative crush is and her answer is swift: "Justin Theroux. Not only is he a great actor but he's one of the best comedy writers out there. And he directs and paints murals." She lets out a racy laugh. "And I just think it's so attractive to be that good at so many things and to have no ego. He's one of the most humble, decent human beings. He's not an ass. He's not like some of our friends who are young and up-and-coming and they hit celebrity, and all of a sudden you're like, 'Oh! You're different. Now you don't say hi to people?' "

Aniston and Theroux originally met "when he was writing on Tropic Thunder. We were just buddies, and then buddies through Wanderlust [the 2012 comedy, in which they costarred]." Now, she continues, "it's almost impossible to get bored with one another. We've tried so hard! And even that's interesting because his eyes are so pretty, but we can entertain ourselves and talk about endless things, which is pretty great."

She also credits Theroux with grace in handling the attention that comes with dating the world's proprietary "Jen." "He's just been doing it so graciously and gracefully, and it's a strange ballpark to walk into. He's in his body, for sure. He's a pretty realized person." She flips back to his career. "But he's been doing this for 20 years."

Of the overwrought 40s, Aniston, 45, observes, "When am I supposed to freak out? When am I supposed to feel like, 'Oh, my knee! Oh, ouch!' I don't feel any of those things! I feel like our aging marker needs to be rejiggered. I heard Halle Berry refer to her pregnancy at 47 as a 'geriatric pregnancy,' which is ridiculous! It's insulting. Obviously, as women we've evolved." She laughs. "My eyesight is shit, though. I already was nearsighted, but now I can't see anything."

Apart from everything, with more clarity: "I've had more fun post-40 than I can remember," Aniston says. "From a work point of view, a physical point of view, a psychotherapeutic point of view." She credits her girlfriends, some of more than three decades, for whom she'd "go to the wall. I'm a pretty good judge of character, shall I say." Before Theroux, Aniston took a break from dating. "It really helped me get to a place where I was more comfortable with myself, truly ready for love and for a partner." She continues, "The past wasn't 'less than.' It was extremely important to my growth as a woman. But if you take the law of attraction, if you only love yourself 70 percent, that's what's going to come back to you. So you fill up that 30 percent, then all of a sudden there's this pure, good love standing right in front of you. Then you realize, 'Oh, this can be easy! It doesn't have to be so hard.' "

The rest of the year will see Aniston launch into promotion for Horrible Bosses 2, out now, in which she reprises her role as a perverted dentist. "It's more hysterical than the first one, and probably a bit darker," she says. Cake was a challenging, dark, deep role, and this was just full-on, like a big ice cream sundae." Cake will be released before the end of the year, so there's a potential awards season to navigate too. "You know, people loved our little film," she says. "That was pretty humbling."

Aniston will, of course, dress for the occasion. Today she's sporting a pair of amethyst earrings: "These are Ted Muehling that my sweetheart got me." Theroux, he of the storied motorbike and leather, has great taste. "He can buy me jeans! I've never had a man be able to buy me jeans." Theroux's urbanity plus Aniston's sunniness equals "ebony and ivory, or tawny and ebony! That's another song altogether."

Finally, and most important, Jennifer Aniston's hair remains incredible. "It's a little darker than normal," she says, giving it a shake, "which I'm liking, actually." Both professionally and personally, going darker is Aniston's best look yet. "But you know," she adds with a smile, "it's just my hair."

This article originally appeared in the December 2014 issue of Harper's BAZAAR.