What is the ruling regarding a wife's feeling of aversion and disgust towards the marital relationship, despite the stability of her marital life and her good relationship with her husband, and her eagerness to respond to him as much as she is able?

There is no sin upon a woman for feeling aversion to marital intimacy as long as she does not neglect her husband's rights. Aversion is a matter of the heart for which one is not held accountable. She is virtuous for responding to her husband despite this aversion, and the causes of this aversion should be addressed.