Gavin O’Connor & Angela Shelton

For Gavin O’Connor and Angela Shelton, a collaborative effort on a screenplay outlasted their brief marriage.

The couple eloped in 1994, shortly after beginning their script for “Tumbleweeds,” a mother-daughter road movie based on Shelton’s autobiographical manuscript. They divorced a year later, but maintained a working relationship for three more years until the script was finished, forging a deep friendship in the process. O’Connor eventually directed the production, set for a fall release from Fine Line; pic stars Tony winner Janet McTeer (“A Doll’s House”).

“The script was our child. That’s how we viewed it,” O’Connor says. “We had so much invested in the story that we put aside our personal problems to continue the relationship.”

Of the two, O’Connor brought more practical moviemaking experience to the effort. He got hooked on films at an early age watching matinees with his dad while growing up in Long Island, N.Y.

He wrote several screenplays and produced two of his own shorts while living in New York, including “The Bet” in 1992, which was Ted Demme’s directing debut. He also wrote, produced and starred in an Off Broadway play, “Rumblings of a Ro-mance Renaissance.” He was looking for a feature project when he met Shelton, read her “Tumbleweeds” manuscript and decided he had found the material for a full-length project.

For her part, Shelton had always liked writing, but fell into a successful acting and modeling career for a number of years. Then she showed O’Connor her memoir about traveling around the country with her mother, who divorced and married several times during Shelton’s upbringing.

“He read it and said, ‘This is a movie.’ He just fell in love with the characters. I said, ‘You’re not doing anything without me,’ ” she recalls.

“After this process, I’ve come out saying that I’m a writer,” she admits. “It’s what I love to do. I love to act, too, so maybe I have to write myself a part.”

She’s finished up her “Tumbleweeds” manuscript and is shopping it around for a book publisher. O’Connor and Shelton also retained TV rights to the “Tumbleweeds” story and are hoping to parlay the script into a series.

Meanwhile, O’Connor, who plays a key role in the film as one of McTeer’s boyfriends, thinks he’s now more of a director than a writer.

“Writing isn’t easy for me. It’s very labor-intensive. It’s a lot more work and perseverance,” he says. “I feel more comfortable wearing a director’s hat. But it’s also a Catch-22 — I need to write something that I can direct.”