AFTER 10 long years of sticking by Sean Combs, the music impresario's baby mama and longtime girlfriend, Kim Porter, has finally had enough.

Sources inside Combs' camp told Page Six that Porter moved out of his apartment here and she isn't going back.

"Kim is in Louisiana filming a movie right now, and when it's done she's moving to L.A.," the insider said.

Porter has already bought a posh pad in Beverly Hills for her and her four children - three of whom, Christian, 10, and twins D'Lila and Jessie, 7 months, are Diddy's.

"She is focusing on her career as a model and actress and raising her children," our source said. "They are the best of friends, but they just can't be together right now."