Leah Remini is standing by Jennifer Lopez’s side as the singer navigates her divorce from Ben Affleck. According to a source, the King of Queens alum’s previous warning to not marry the dad-of-three “pretty much ruined their friendship the last couple years,” but now that Lopez is single again, the women are “back on great terms.” Since they’re “closer than ever,” Remini, 54, has “assumed being J.Lo’s de facto divorce coach.” “She’s more than happy to take it on and give her all the support she needs,” the source continued to tell a news outlet. “All of J.Lo’s friends are disgusted by Ben righ…