Where in that sentence do you get the idea that he "stopped 'making smalltalk'" after "they told [him] they had a boy/girlfriend"?
Because since he now knows she has boyfriend, therefore he is not hitting, therefore logically she is unlikely to interpret further conversation as hitting. Incidentally, that is remarkably similar to the way people on spectrum "logically" interpret humans - have hard time imagine other person perspective (here he knows he is not hitting therefore she knows too) - and get into trouble despite really not having bad intentions.