How does Dorothy L. Sayers use imagery in Gaudy Night?

Imagery:

She wondered whether her lover had seen it like that, through the hot unhappy years when she had tried to believer that there was happiness in surrender. Poor Philip—tormented by his own vanities, never loving her till he had killed her feeling for him, yet perilously clutching her as he went down in to the slough of death.

She could feel his bone and muscle, reassuringly human, under the fine broadcloth. She thought: "He and I belong to the same world, and all these others are the aliens."