"Neither of us thought our marriage was going to make it," she told PEOPLE. "I think we both sort of had this feeling that when the kids left [for college], we'd give it one last shot and that would be that."
"There were points when we didn't even want to give it one last shot. It was intense and volatile," she continued, adding that the couple had simply begun to grow apart over the years. "We really were headed in a dark space."
Meredith says it wasn't until she and Seth told their three children about the separation and began seeing a marriage counselor that they decided to "try and start over."
"We really starting to work through things with a marriage counselor to see if there was something worth saving," she said. "We agreed that we do need room, we do need to live separately, but there's hope, and let's see if we can make it happen."
Meredith and Seth wed in 1996. They share three adult children, Reid, Chloe, and Brooks.
Photo Credit: Instagram/Meredith Marks