Walking through the story, perhaps with a fair dose of confirmation bias, he recounted that every time he was nice to her, said loving things, did a little extra, she backed up or said something that was perceived as mean. Coached to ask her to clarify, he did.
"Why bother being nice to people, if they treat you poorly when you do? I get treated well and I reciprocate and I get consequences or punishment, or so it feels. Karma aside, what is the point of being nice and decent to people?"
We talked at length about the motivation for behavior. Is he being nice to people to get something in return (a transaction)? Or is he being nice because that is who he is?
Part two of the conversation is to look critically at his assumptions and look for exceptions. Are there cases wherein he is nice and kind and people reciprocate? Does he himself feel better when so doing? Is it possible that he is feeling the sting of a couple poor interactions and generalizing them to all?
Is it possible that there is another dynamic at play and he is not seeing it clearly? What if he is being super sweet to her and she simply cannot accept or receive that kind of love? She has to bring him down a notch but does not have the verbal precision to articulate her point. What if she is communicating that it is too soon or that he stepped over a line of hers that he is unaware of? Is it possible that he put himself in the friend zone without realizing it?
What else could it be?