The Immediacy of Pain

The things she did she said that she did them out of love (the violence, the conflagration). Which is to say, the things that she said that she did not do to those other men (nothing much at all) were things she had been able not to do because she did not love those other men, she said.

In other words, K thought to himself, she cannot harm somebody she does not care about.

They had much in common, which is why they loved each other.