Kristen Stewart on July 22, 2012 in Universal City, CA; Jules Stewart on August 8, 2012 in Los Angeles, CA. Credit: Jason LaVeris/FilmMagic,Coleman-Rayner

While Kristen Stewart's relationship with Robert Pattinson has been on the rocks so has her parent's marriage.

According to TMZ, Kristen's mother Jules Stewart filed for divorce from John Stewart on Aug. 17 in L.A. County Superior Court. The Twilight Saga: Breaking Dawn - Part 2 star's parents have been married for 27 years.

Jules, a writer/director, cited irreconcilable differences in her filing and listed the date of her separation from John, a TV producer/stage manager, as June 15, 2010, TMZ reports.

Stewart, 22, has had her own relationship issues with boyfriend of three years Pattinson, 26, after she was caught cheating on him with her Snow White and the Huntsman director Rupert Sanders, 41, last month.

"She isn't sleeping and she stays up all night crying," a source recently told Us Weekly of Stewart. "She's close to a total meltdown."

Will the Twilight costars be able to work things out and stay together?

"Right now their relationship isn't defined," an insider told Us earlier this month. "Rob's dealing with a lot of indecision . . . "