Did Patrick Dempsey's obsession with fast cars end his marriage?

Add speeding to the list of things that can drive a wedge right through a marriage.

Radar Online is reporting that Grey's Anatomy star Patrick Dempsey's love of car racing might be the main reason why his 15-year marriage to Jillian Fink just ended. Seems those 15-hour workdays on the Grey's set weren't the only thing cutting into family time.

"Jillian often complained to friends that Patrick would be unavailable to attend their children’s activities," a source said of his demanding racing schedule. The couple have two children, daughter, Talula, 13, and twin sons, Darby and Sullivan, 8.

The 49-year-old actor was out of town for yet another race while his wife was officially ending their marriage, but apparently his frequent absences were just part of the car problem.

"Jillian was constantly worried Patrick would become injured while driving," the source added. "Those cars go so fast, and that also added to the stress of the marriage."

Whoa, slow down there, McDreamy!

Adding insult to potential injury, Jillian was the one who set her husband on the fast track.

"Jillian had signed Patrick up for race car driving school, thinking it would be a fun hobby for him to have," the source revealed. "She had no clue Patrick would become such a racing enthusiast and even form his own driving team!

"Jillian regrets having encouraged it in the beginning. Race tracks in pit row aren’t exactly family friendly or safe for kids to be around."

Suddenly, a simple necktie is beginning to seem more like the perfect gift.