Jason Mewes says he hasn't heard from Ben Affleck in a while now ... but, he's not taking it personally ... explaining everyone gets busy and wishing his buddy the best. We caught up with the actor in Los Angeles, and ask about his old friend ... inquiring if he'd checked in on Ben since telling…

Ben Affleck's close friend Jason Mewes ain't buying into the swirling speculation the actor's marriage to Jennifer Lopez is crumbling ... not based on what he's seen. We got Jason out Wednesday in L.A., and he told us after witnessing Ben and Jen's genuine affection at their wedding less than 2…