"The marriage has become insupportable because of discord or conflict of personalities ... that destroys the legitimate ends of the marriage relationship and prevents any reasonable expectation of reconciliation," Buffington states in her petition. Her rep confirms that she's filed for divorce, with the court documents submitted March 2 in Texas.
The couple, who were hand in hand at the Sundance Film Festival in late January, married in 2004 and are parents to 4-year-old twins Thomas and Zoe.
Buffington, a real estate agent, is seeking spousal support, attorney's fees and a fair division of their community assets (they are currently selling their Montana ranch for $14 million). Quaid, in his response, offered to pay his missus the sum total of zero dollars.
The petition also contains language that ensures the split will remain civil, ordering the estranged couple to avoid using words with each other that are "vulgar, profane, obscene or indecent."
They are currently sharing custody of the twins, who nearly died shortly after they were born due to a hospital error (they were given an overdose of the drug Heparin; the actor successfully sued and became a health care advocate).
Other tidbits from the documents reveal that Kimberly will retain use of the family home and Mercedes, while Dennis gets a condo and a Cadillac Escalade. They'll apparently have to share use of their Range Rover.
No word on when the couple officially called it quits, but Buffington's filing comes on the heels of a New York Daily News report that accuses Quaid of wooing another man's date during a Valentine's Day party at Serena Williams' Los Angeles home.
In several since-deleted tweets, the tennis champ's practice partner, Sascha Bajin, apparently alleged that Dennis swooped in and put the moves on the woman he was with. At the end of the night, the actor supposedly asked for a ride back to his hotel, and Bajin's date got out of the car with him.
"He stole my date and made me drive him and her to his hotel," Bajin reportedly wrote. "I simply got Quaided … Lol!"
This is Quaid's third marriage. His previous unions, to Meg Ryan and P.J. Soles, also ended in divorce (in 2000 and 1983, respectively).
"Dennis was not faithful to me for a very long time, and that was very painful," Ryan told In Style magazine in 2008. "I found out more about that after I was divorced."
Meg, of course, had a very public hookup with her "Proof of Life" star Russell Crowe, which ended up torpedoing not just her marriage to Quaid but also her reputation as America's sweetheart.
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