09/16/2009 at 01:00 PM EDT
Expecting diva-like antics from Jennifer Aniston
? No way, says her costar in the upcoming Love Happens.
"She was very easygoing, very effortless," Aaron Eckhart, 41, told PEOPLE at the movie's premiere in Westwood, Calif., Tuesday. "I think that's the word I want to use: effortless."
He explains, "She keeps good people around her. She's interested. She asks questions. She gets outside of herself and lives, I would say at the very least, an interesting life. It's not really always her own. She deals with it very well."
In between photo ops with Eckhart, Aniston, 40, attended Tuesday's premiere solo, smiling, taking pictures with fans, signing autographs and talking to press – though she kept her chatter brief.
"Love – that's what I love about love," Aniston told reporters. "That's it."
She described Love Happens
, her romantic drama-comedy with Eckhart, as "a really good experience. Moving. See it. You'll see why."
Costar John Carroll Lynch told PEOPLE, "I love that she suffers in this fishbowl of life, and I find her intriguing. I find it extraordinary."