She ties the dressing gown around her waist. Lines up her toes where the metal coping separates the hallway carpet from the bathroom tiles. A diver’s stance. Anticipation of the tiles’ coldness.
She steps. Plummets. Side steps the bath mat. Plants her feet squarely. Small ripples quickly subside. The cold tiles prickle the soles of her feet until it stings. Tapers off to an equilibrium.
Repeatedly she will lie on her back on the bathroom floor undressed. Lets the cold of the tiles fight with the heat of her body. She relents. Acquiesces. Adds a layer of permafrost to her heart against the fire of her mother’s tongue.
A Fullness in Brevity - Adam Byatt 
i love both the angularity of the imagery and the sound of the words too in that first paragraph
The language was beautiful, but I was a little confused as to what actually happened.
I seem to have failed in this instance to communicate my ideas.
Remember how tiles feel cold under your feet, especially in winter. The character is stepping into the bathroom in bare feet, letting the coldness attack the soles of her feet.
In the second half of the narrative, and this is where, on reflection, word choice has confused the imagery, the character returns time and again during her years to lie on the coldness of the tiles as a way of protecting herself from the hot, harsh words of her mother.
ok, so she’s literally doing that? I wasn’t sure if it was a mental thing or not. Thanks for the clarification. ☺