How we cite our quotes:
As soon as he touched her she seemed to wince and stiffen. To embrace her was like embracing a jointed wooden image. And what was strange was that even when she was clasping him against her he had the feeling that she was simultaneously pushing him away with all her strength. The rigidity of her muscles managed to convey that impression. She would lie there with shut eyes, neither resisting nor co-operating but submitting. It was extraordinarily embarrassing, and, after a while, horrible. But even then he could have borne living with her if it had been agreed that they should remain celibate. But curiously enough it was Katharine who refused this. They must, she said, produce a child if they could. So the performance continued to happen, once a week quite regularly, whenever it was not impossible. She even used to remind him of it in the morning, as something which had to be done that evening and which must not be forgotten. She had two names for it. One was "making a baby," and the other was "our duty to the Party." (1.6.13)
Winston hated having sex with Katharine because of her mindless devotion to the Party.
Winston sighed inaudibly. He picked up his pen again and wrote:
She threw herself down on the bed, and at once, without any kind of preliminary in the most coarse, horrible way you can imagine, pulled up her skirt. (1.6.14-15, Winston)
Sexually repressed to the extreme, Winston employs prostitutes to quell his urges.
He saw himself standing there in the dim lamplight, with the smell of bugs and cheap scent in his nostrils, and in his heart a feeling of defeat and resentment which even at that moment was mixed up with the thought of Katharine's white body, frozen for ever by the hypnotic power of the Party. Why did it always have to be like this? Why could he not have a woman of his own instead of these filthy scuffles at intervals of years? (1.6.16)
Winston resents the Party because Katharine’s devotion to it repressed him sexually.