Just months after rescinding on her move to file for divorce, Dennis Quaid‘s wife Kimberly Buffington has filed for legal separation. According to TMZ, this is only a formality and the documents will be changed to divorce docs in the next several moths.

Buffington is asking for joint legal and sole physical custody of the pair’s 4-year-old twins.  She also wants spousal support and for Dennis to pay her attorney fees.

A source close to the couple says “Kimberly is fed up with Dennis’ cheating and wants out of the marriage.” The source added, “He’s not a good husband.”

“Kimberly and Dennis Quaid have decided to legally separate after 8 years of marriage. They ask that their privacy and the privacy of their family be respected during this difficult time,” a rep for the actor said Friday.

The reason for a separation filing and not a divorce filing is due to the fact that the couple moved to California during the summer. And in the state of California, you must have a 6-month occupancy before filing.

If the divorce goes through this time, this will be Dennis Quaid’s third divorce. He was previously married to Meg Ryan and PJ Soles.