Jennifer Garner seems to be over Ben Affleck’s drama with Jennifer Lopez. According to insiders, as the Argo star, 51, continues to figure out his life amid his alleged split from the “Get Right” singer, 55, his ex-wife, 52, is done trying to help him. “Jen let Ben know it’s his mess to clean up alone — and she’s out of it,” the source spilled. “He’s officially on his own.” The staunch warning came as Garner’s longtime boyfriend, John Miller, reportedly put his foot down when it came to the Alias actress going above and beyond for Affleck. “John is tired of weekends and holidays he could be sp…