A broad-brush, sociological analysis of the book reveals that it's a story that features an `individual-versus-society' theme, raising the usual thought-provoking questions: Can individuals flaunt with impunity the unwritten laws of society? Can they break out of the mold in which society has cast them? Or do they, for all their valiant efforts, end up affirming the truth of the Japanese proverb: `The nail that sticks out will be hammered down'?
Here, you have Edna Pontellier, a married Creole woman of the late 19th century who, by a confluence of circumstances, realizes that she's been straitjacketed by conventions all her life and thereafter resolves - without much thought of the consequences - to free herself from the chokehold of a bland existence and give full form and substance to her intellectual, artistic, emotional, and sexual proclivities. She thus takes a series of bold, reckless steps in this direction, and not even the sweet joys of parenthood or the discreet interventions of friends like Adele Ratignolle and Dr. Mandelet can hold her back. Indeed, she finds herself incurably captivated by the prospect of attaining full independence (and by implication, gaining unqualified affirmation of her individuality); she's drawn to it like a moth to a flame.
Not surprisingly, however, her precipitate transformation heightens her sense of isolation even as it gives her a sense of empowerment. The more she becomes more of herself, the more her sense of attachment to others unravels. Unfortunately for her, the trade-off between independence and isolation takes on the character of a Faustian bargain, and consequently, her situation becomes increasingly unbearable. Things come to a head when Robert Lebrun, for whom she has felt the stirrings of passion, eventually, reluctantly, reveals his affection for her but proves unable - or unwilling? - to act on it. Unlike her, he is still pretty much a product of the society in which he has been bred. He can't - or won't? - bring himself to defy communal expectations by having an illicit affair with her no matter how much he loves her, no matter how much she wants it. And this turn of events proves to be the proverbial last straw, predisposing her to kill herself.
In view of the ending, how then should one interpret the story? Is this a resounding triumph of society over a defiant individual? Or is this a tragic yet heroic struggle of a defiant individual? It's all a matter of perspective, I reckon. Those who regard Edna Pontellier's transformation as a mutation will say it's about the dire, social consequence of individual maladjustment, of an individual's misguided desire to defy social conventions in pursuit of self-reinvention. On the other hand, those who regard it as a metamorphosis (yours truly included) will say it's about the provocative assertion of individuality in the face of overwhelming social constraints; it's about an individual who has tired of playing by the stipulated rules of the game, as it were, and dares to quit for good - and does so to good effect.