A young woman had been married for three years and lived with her husband in Val de Ciré, where he owned two cotton mills. They led a quiet life, and although they had no children, she was happy. Her husband was much older than her, but he was kind and she loved him.
Every summer, her mother would visit them, and then return to Paris for the winter.
The young woman developed a cough, and the doctors advised her to spend the winter in Paris with her mother. At first, she missed her quiet life in Val de Ciré, but soon she began to enjoy the social life in Paris. She attended dinner parties, balls, and other events, and men paid her a lot of attention. She found their advances amusing and felt confident that she could resist them.
Two men in particular were persistent in their pursuit of her. One was a tall, confident man named Paul Péronel, while the other was a shy, gentle man named Monsieur d'Avancelle.
She treated the former with amusement and the latter with kindness, eventually making him her devoted servant.
One night, she had a vivid dream in which she and Monsieur d'Avancelle were deeply in love. When she awoke, she found herself obsessed with the memory of the dream and began to feel a strange tenderness towards him.
She loved him, loved him with a strange tenderness, refined but sensual, chiefly from the remembrance of her dream.
She confessed her feelings to him, and they spent hours together, sharing chaste kisses and enjoying each other's company.
However, she knew that she could not resist him forever, and decided to return to her husband in Val de Ciré. Her husband advised her against returning in the middle of winter, but she insisted. One evening, before she left Paris, she went for a drive with Monsieur d'Avancelle. They shared passionate kisses, and she knew that she was lost.
When she returned home, she found Paul Péronel waiting for her in the dark. He spoke to her tenderly, and in her confused state, she believed that he was Monsieur d'Avancelle. She allowed him to embrace her, but when she realized her mistake, she was horrified and sent him away.
The next day, she returned to Val de Ciré and her husband. She was changed, sadder than before, but when her husband asked her what was wrong, she simply replied that happiness only exists in dreams.
Happiness exists only in our dreams in this world.
When Monsieur d'Avancelle visited her the following summer, she felt no emotion for him, realizing that she had only loved him in her dream.