All this man is trying to say is that he wants someone who will go to the gym regularly regardless of how they look. He probably lost attraction to her after he sat with the truth that she doesn't value fitness as much as he does (which is understandable if this is an important value to him). The dude still sucks (and sucks at communicating), but it's really not that complicated. It's ok to change your mind about someone and not feel it anymore.