I would agree with that assessment, but only insofar as the girlfriend has created a self-fulfilling prophecy. She's conjured a problem out of thin air, where one doesn't actually exist. By feeding into that delusion there's no reason to assume she won't do so again in the future, be it about a coworker or even a random woman on the street. I agree with Winter Blossom, it's not healthy in the long run.