Unwell, lovesick, Or Truly Changing?

Edna seems to have finally torn away pieces of a "mask" she wears in order to maintain her content, and yet impassionate life with her husband.  She does not seem to be actively doing so, but rather to be doing so out of pure emotion due to the fact that Robert has departed for Mexico.  Simply, she cannot control herself, and seems to be lovesick, longing.  Why is Edna finally truly becoming "Edna?"  That is, why has she stopped hiding her passions, her ideas, and her sense of self behind the idea that she is Mrs. Pontellier?  She even begins to act differently at home, leaving he house on calling day, taking up painting, and associating with people of which her husband is not fond.  Is Robert truly the cause of such change, or is he rather just the trigger?
Is Edna truly misbehaving as a wife as Mr. Pontellier believes (by both today's standards, and/or the standards of the time)?  Why does no one else seem to notice or fault her "strange" behavior?  Consider that even the doctor recognizes that the behavior is not the behavior of an unwell person, but rather that of a discontent woman.  He mentions that perhaps she just needs space, and considers to himself that there might be another man.  What, then, should one make of her behavior, and what does it truly look like?
Overall, is Edna truly lovesick for Robert?  Could she perhaps be unwell, as her husband has suggested?  Could she be simply growing out of a phase, or changing in personality?
Perhaps Edna is unwell, lovesick, and truly changing.  That is, perhaps she truly does love Robert, or in the least had come to love his company and attention.  By becoming infatuated with that attention and company she was certainly "lovesick."  She perhaps became unwell when that bloomed into more of an unhealthy want for his attentions (for a married woman, that is) and in a way, she became unwell with searching for a way to keep his affections, to maintain a connection with him.  This sickness perhaps made her unable to use thought and self control to maintain her emotions, and thus caused a change in her behavior, perhaps a change in herself overall. 
Then again, perhaps she is simply sick of her husband and his "over attentiveness." 
What, then, caused such a behavioral change in Edna?