The timely Sundance film expands on the gay marriage discussion.

PARK CITY, Utah — Concussion’s world premiere at Sundance couldn’t have been more fortuitous, given President Obama’s support of gay civil rights in his second inaugural address on Monday.

The film deals with a wealthy lesbian couple whose longtime marriage hits the skids when one of the partners is hit in the head with a baseball and starts to re-evaluate whether she wants to continue to live the suburban life.

“It’s certainly timely,” says writer/director Stacie Passon. “All of this really calls out the idea that this (gay and lesbian) community has been searching for legitimacy for a long time. And all the hard work has really paid off.”

Fittingly, on the day of Obama’s speech, a studio arm of The Weinstein Co., Radius, announced it had purchased the film for distribution. Concussionis now slated for an early fall 2013 release.

Concussion is not a romantic picture of marriage by any stretch. But it deals with the real issue of what happens when the marital flame goes out.

The injured partner, Abby (Robin Weigert), decides to give up the world of minivans and start a new life as a high-end lesbian prostitute in Manhattan.

“It’s a concussion-like midlife crisis,” says Passon. “It hits you hard. And suddenly the rules don’t make sense anymore. This is a real side of what marriage is all about.”

The real-life struggles of same-sex relationships have been explored in-depth in films such as Lisa Cholodenko’sThe Kids Are All Right (2010).

“It sort of stands on their shoulders, totally,” says Passon. “I don’t think without Lisa’s movie that we could have told the story as effectively. This sort of deepens the conversation.”

The film idea has a clear origin: Passon has been married to the same woman for 20 years, and on her 40th birthday three years ago she was beaned in the head with a baseball thrown by her son.

“It was much the same way as in the movie. And it put me into this place of ‘This is crazy. I don’t want this life anymore,’ ” she says. “You love your family, love the choices you have made, but you long for something else.”

However, Passon did not go to the extremes that her film character takes afterwards, saying her biggest thrill was heading to Sundance to sell her film.

Concussion has received support from the gay and lesbian community, but Passon feels the universal theme of marital woes will reach an even larger audience. And the film received a warm reception at Sundance despite the conservative surroundings in Utah.

“This is a hippy gay and lesbian haven for 10 days,” says Passon.

The director says she has not come face-to-face with critics of the film and feels the voices against gay marriage are being overwhelmed by the supporters.

“That dissenting voice is waning. It’s hanging on by a thread. There’s a majority that embrace it,” she says. “I think there’s a broad audience for this film. I think all people will be able to relate to the time when the love dies.”