It was a curious game. This curiousness was evidenced, for example, in the fact...

It was a curious game. This curiousness was evidenced, for example, in the fact that the young man, even though he himself was playing the unknown driver remarkably well, did not for a moment stop seeing his girl in the hitchhiker. And it was precisely this that was tormenting. He saw his girl seducing a strange man, and had the bitter privilege of being present, of seeing at close quarters how she looked and of hearing what she said when she was cheating on him {when she had cheated on him, when she would cheat on him}. He had the paradoxical honor of being himself the pretext for her unfaithfulness.
This was all the worse because he worshipped rather than loved her. It had always seemed to him that her inward nature was only within the bounds of fidelity and purity, and that beyond these bounds she would cease to be herself, as water ceases to be water beyond the boiling point.