One way of responding to this question would be to focus on the historical context of the novel and the way in which the 19th Century saw an increasing change in the status and importance of women. The Women's Rights Movement really begain in this century, and argued for women to be recognised as having their own needs, desires and identity as separate to their husbands and protested against the injustices of a patriarchal world. Thus we can argue that Edna's response to her "awakening" and the discovery of her own desires and wants reflects the stirrings of many women at the time, who found themselves stifled as individuals and women in a man's world and desired the freedom that Edna tried to gain for herself.
Edna's transformation throughout the novel therefore mirrors the sense of rising indignation and self-discovery that many women underwent. A revealing quote comes in Chapter 19, where Mr. Pontellier comments on the changes in his wife:
It sometimes entered Mr. Pontellier's mind to wonder if his wife were not growing a little unbalanced mentally. He could see plainly that she was not herself. That is, he could not see that she was becoming herself and daily casting aside that fictitious self which we assume like a garment with which to appear before the world.
Here we see a man's view of his wife's own increasing sense of self, regarding it as being symptomatic of mental insanity. He is blind to the way in which the wife he knows has not actually been Edna's true personality, but a mere "fictitious self" that she has assumed to fill the expectations of society. Edna's casting off of this "fictitious self" thus provides a parallel with the rising sense of injustice experienced by many women in the 1800s.