Motherhood almost kept Nicole Kidman from finishing her latest film, Rabbit Hole. At Saturday's (Jan. 8) post-screening Q&A at Nashville's Belcourt Theatre, the Oscar-winning actress said if she had been a parent herself at the time, she may not have taken the role of a mother who loses her 4-year-old son in a car accident.

Kidman was not yet pregnant when she first became aware of David Lindsay-Abaire's play after reading a New York Times article while sitting in a Starbucks just outside of Nashville. As Kidman explained, it took more than four years to produce and shoot the movie. During that time, she and husband Keith Urban welcomed their daughter, Sunday Rose.

Acknowledging her Golden Globe-nominated portrayal of Becca in Rabbit Hole was a "terrifying" experience, Kidman said she still gets very emotional when thinking about the story. She said the role "still sits in my psyche and probably will forever."

Seeing the play prior to filming was not an option for Kidman.

"It would have intimidated me," she said, noting that co-star Dianne Wiest saw the play in New York City and turned down her role as Becca's mother four times before finally agreeing to do the film.

Kidman produced the movie for $3.5 million.

"That's low-budget filmmaking," she said.

Financial considerations affected her choices for music in the film. When one fan asked about her decision to use Al Green's "Lay It Down" in a scene where her husband (portrayed by Aaron Eckhart) tries to seduce her, Kidman laughed, "That was the cheaper Al Green song. We wanted to use 'Simply Beautiful,' but it was too expensive."

Wearing the producer's hat also gave Kidman an appreciation for what she may have put other filmmakers through when deciding whether or not to work on a particular project.

"Before, I might have read a script, got distracted and let it sit for a while," she said. "Now I've learned to read a script and give an answer much sooner because the waiting is hard."

When one attendee at the screening pointed out Kidman's apparent willingness to turn down projects in recent years, the actress hinted her current real life roles as mother and spouse could be to blame.

"Early in my career when I was working a lot, I was not very happy in my real life," she said. "Now I am extremely happy."

In addition to Rabbit Hole, which opens nationwide on Thursday (Jan. 14), Kidman will have a lighter role in the Adam Sandler comedy, Just Go With It, set for release on Feb. 11.