[He does hear the slight tremolo in her voice, but he chooses not to say anything. Instead, he tries a different approach, trying to understand all the mixed messages she's been sending him]
I know you did. But in all honesty, Cornelia, can you really tell me that it's impossible because you're not interested in relationship or because you're really not interested in me?
[He knows he's taking a chance there. He might be assuming too much of all their previous times together. But somehow, he needs to know the truth. And he knows Cornelia enough to expect her not to be entirely honest with him.]