01/21/2012 05:32 pm ET Updated Mar 22, 2012

'Celeste And Jesse Forever': Rashida Jones Talks Relationships, Writing, 'Bugging Out'

Rashida Jones is one of the early stars of the Sundance Film Festival, and not just for her acting.

The star is both the lead and the co-writer of the relationship dramedy "Celeste and Jesse Forever," which marks her screen-writing debut. She penned the script with fellow actor Will McCormack, then spent years trying to jump over Hollywood business hurdles to get it produced. The film premiered Friday at Sundance, making for quite an intense experience for Jones.

"That was like an extra-terrestrial experience," she told USA Today after its big first screening on Friday. "We were just bugging out at the screening."

The film features Jones and "SNL" star Andy Samberg as a pair of divorcing high school sweethearts trying to navigate complicated love lives while remaining friends. It also features supporting turns from Elijah Wood, Ari Graynor and Emma Roberts.

The picture is personal for Jones beyond just her multiple appearances in the credits; as she told The Hollywood Reporter, the story is based in part on different relationships in her own life.

"It's definitely a pastiche for both of us. We talk all the time about relationships and love and what it means and how it changes -- what it means to grow up and how that affects the way you love people," Jones said. "We're kind of obsessed with it! The film is for sure emblematic of a couple relationships I've had; some of them romantic and some of them friendships. It definitely reflects my relationship with Will and other guy friends I've had from the time I was 15. Definitely a mashup all around."

And of course, as with any film about relationships, it wasn't always the most fun thing to write.

"There's no better way to process pain than to write. I've not had that experience with acting," she explained. "I mean, you can momentarily get these glimpses of real pain, but it's nice to really, really process it and get into it and figure out why it hurts so bad; be really honest about it without having it be you talking to the person you want to talk to."

For more from Jones on the film, including talk about Samberg, how she got the film made and more on her experience writing, click over to The Hollywood Reporter.