The "Stand by Me" star was around the couple when they first started dating and, like many fans, he was completely blindsided when Arquette and Cox confirmed they had split in a statement on Monday.
He says, "That David Arquette/Courteney Cox news was shocking, man... I never saw that one coming... and it's sad."
And he jokes he and his wife Rebecca Romijn could be next - but their twin girls are keeping them together: "My wife and I have really talked and thought about splitting up but we're too afraid that one of us is gonna get stuck with the children, so we stay together.
"If it weren't for our kids... it would be done. We'd have one of those open Cox/Arquette relationships."