Describing herself, the protagonist says,
I love the laconic. Clearly, I am not of their number. When animated conversations are going on, even with people interrupting one another, I have to curb an impulse to field every remark, by everybody, as though it were addressed to me. I have noticed this impulse in other people. it electrifies the room.
Later, the protagonist says,
There are, however, people who just sit there, silent. A question is addressed to them. They do not answer. Another question. Silence. It is a position of great power. Talkative people running toward those silences are jarred, time after time, by a straight arm rebuff. A quizzical look, a beautiful face perhaps, but silence.
I read this as an excellent articulation of why and how silence can be used as an intervention, as an act, when one is listening to a neurotic.