"Things couldn't be better," the actress, who recently split from John Mayer, told PEOPLE at Sunday's screening of her new film, Management, at the Toronto International Film Festival. "Busy, but it's great."
Asked where she finds her inner strength, Aniston, 39, told reporters, "Waking up everyday."
Indeed, her Management director, Stephen Belber, said Aniston is naturally optimistic. "She has great strength, and I never heard her complain. Not once," said Belber. "There was never a sign of, 'Oh, poor Jen.' She has a positive outlook on things. She is the most upbeat, thoughtful, sincere person."
Dressed in a sleeveless black Balenciaga cocktail dress, Aniston caused quite the commotion with throngs of adoring fans. "It's great to see people come out and support the film," Aniston said of all the attention. "So far, I'm having a ball. It's lovely to be here."
Guest AppearanceOne project keeping Aniston busy, in addition to promoting her movie, is her upcoming appearance on NBC's 30 Rock, which she filmed recently.
"It was awesome – really, really fun," she told Entertainment Tonight about working with the show's "stellar" cast.
Of her comedic role in which she plays a Fatal Attraction-like stalker, she revealed, "I manhandle a cop. But I won't give away the ending. It was fun, but I somehow don't get into jail."
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