Edna moves into full-fledged rebellion. She abandons all social and household duties, spending time instead painting in a small studio she's set up on the top floor of their house. As she paints, she mentally recalls the details of her time with Robert and sings the song "si tu savais" which he sang to her. Her consistent insubordination causes Léonce to wonder about her mental health.
Edna's lack of true artistry is further depicted in this chapter. On her bad days, "when life appeared to her like a grotesque pandemonium," she is not inspired by the darkness of human experience and emotion, as the great painters are. Instead she paints when she is happy, reveling in the sensuality of existence when "her whole being seemed to be one with the sunlight, the colors, the odors" of her world.
These extremes of emotion do satisfy her newly insistent desire for a life passionately lived. In that respect, Edna has gotten what she wants.
Edna admits her lack of artistry to Léonce, agreeing with his assessment that she is not in fact a true painter. Yet Léonce's insight ends there; he feels she is possibly losing her mind when she is, in reality, finding her true self, a self that rejects the role of housewife and the pro-forma socializing that accompanies her role in society.
en bonne ménagère as a good housewife.
atelier a studio or workshop, especially one used by an artist.