Promoting his new TNT series Franklin & Bash at an Armani Exchange/ Elle magazine event on May 25, Mark-Paul Gosselaar seemed a far cry from Zack Morris, his fun-loving character on Saved by the Bell. “He looked somber,” an insider tells In Touch. “He and his wife are separated,” adds the insider about the actor, who married his wife, Lisa Ann Russell, 13 years ago after she guest-starred on Saved by the Bell: The College Years. Recently, Lisa has been spotted out “partying around LA,” the insider says, while Mark-Paul has been staying home with their children, Michael, 6, and Ava, 4. “He’s taking it very hard,” the insider adds. Mark-Paul used to be the one out partying after he became a teen idol starring on Saved by the Bell. But after marrying Lisa, “Having children made me mature,” he has said. Now, while Mark-Paul is focused on his children and his career comeback, Lisa seems to be on a different page. “This has been going on for quite some time now,” says the insider.