All of a sudden, he hates being here with her, eating "deluxe" at this cheap restaurant. He hates that he has shown his emotional cards, as it were. He hates that he has revealed that he is still sensitive about their relationship. Or their former relationship. He hates that she has just said, and rather pityingly, at that, Oh, Alex.
He hates it all the more because it still feels as though she is leading him on. As she did before. And she is leading him on. He needs her to guide him through whatever this is. Whatever this is.
He sees the ... irony? No, that's not quite the word for it... he sees the... complementarity of it? The symmetry?
She is leading him on, but she is not leading him on.