Dennis Quaid and wife Kimberly Quaid arrive at the 68th Annual Golden Globe Awards held at The Beverly Hilton hotel on January 16, 2011 in Beverly Hills, California. Credit: Frazer Harrison/Getty Images

All good things come to an end.

Real estate agent Kimberly Buffington-Quaid has filed for legal separation from actor Dennis Quaid, her husband of eight years, TMZ reports. She is asking for joint legal and sole physical custody of their 4-year-old twins, Thomas and Zoe.

(The siblings almost died as newborns in 2007 when the medical staff at Cedars-Sinai Medical Center accidentally gave them an overdose of the drug Heparin. After filing a lawsuit with the hospital and the drug manufacturer, the couple was awarded $750,000.)

Repped by power attorney Laura Wasser, Buffington-Quaid is also seeking spousal support and legal fees. She first filed for divorce in March 2012 but withdrew her petition two months later. "Kimberly. . . wants out of the marriage," a source close to the couple tells TMZ. "He's not a good husband."

Prior to marrying Buffington-Quaid, the Vegas actor, 58, was wed to Sleeping in Seattle star Meg Ryan, 50; they divorced in 2001 and are parents to Hunger Games star Jack, 20. Quaid was first married to Halloween actress PJ Soles, 62; they divorced in 1983.