She remembered things Fraeulein Hirsh had said.
"I could not marry you--if I were to be killed because I didn't," was all she could say.

Because marriage had meant only Donal and the dream, and being saved from the world this one man had represented to her girl mind.
"You say that because you have no doubt heard that it has been rumoured that I have a depraved old man's fancy for you and that I have always hoped to marry you.

That is as false as the other story I denied.

I am not in love with you even in an antediluvian way.

You would not marry me for your own sake.