The former Grey's Anatomy star's wife Jillian Fink filed for divorce in January 2015 after 15 years of marriage. However, in a turn of events the pair, who have three children together, called off the split and are now celebrating 18 years of marriage.
"Happy 18th anniversary @patrickdempsey!," she writes on the social media site. "Through thick and thin... I love you~ wifey."
Last year, the Grey's Anatomy star opened up about what he was doing to get his marriage back on track, including cutting back on car racing.
"You can only do one thing at a time and do it well," he explained to People magazine. "I (learned) to prioritise. Our union has to be the priority. I wasn't prepared to give up on her and she wasn't either. We both wanted to fight for it.
"You've got to keep at it. You've got to communicate, and stay open and not get lazy. And not give up. And lots of sex!"
Patrick continued to explain he wasn't ready to throw in the towel, and was confident he and Jillian could do more to save their nuptials. Although it was a "scary" time, the 51-year-old knew he and his wife had to do their best for their kids.
"It's always destabilising when you're potentially breaking up a family or you have a big section of your life that's ending," he recalled.
"Everybody has their own path. Jill and I decided it was time to work on our issues and improve. We wanted to be role models for our kids like, okay, if you have differences, you can work them out."