"The Story of an Hour" (Kate Chopin):Descending the stairs with her sister was supposed to be the beginning of her new life. Instead it was cut...

I think Chopin uses her female characters' deaths as a means to freedom.

In The Awakening, Chopin's most famous protagonist, Edna Pontillier, commits suicide by drowning herself.  She too was confined by patriarchy, social institutions, and gender limitations.  She consciously chose death because it was one of the few aspects of her life that she had complete control over.  As such, she felt that the society was so corrupt that death was preferred to it.

Other critics agree that Chopin uses death as a means of freedom:

Edna has slept for years and years. She slept through motherhood, through marriage, and though most of her adult life. When she was enlivened, it was by a mirage. She followed this apparition, aspiring to a life she could (in reality) never achieve. But how can a woman conceive of these things and then forget? Once our consciousness has been roused we cannot snuff that candle, put in on a shelf, and return to a life in darkness. Edna has been awakened; she has realized the unjustness of life, and of her own role in it. With this new awareness, there was no way for her to continue the current charade she participated in. There was also no way her world would have allowed her to pursue the notions of independence and freedom she had perceived. The social roles she was trying to break away from would never really have released her. "Leonce and the children…were a part of her life. But they need not have thought that they could possess her, body and soul" (137). I find myself wishing that she had never opened her eyes; that she could have lived out her days blissfully ignorant of the circumstances which bound her. This being impossible, even more than the idea of a life of her own, Edna chose the only possible option to escape from an existence full of unfulfilled desires and unhappiness.

Edna re-enters the sea; scene of her first taste of power and emancipation. She returns because it offers her the only other possible freedom she is allowed; the freedom of death. It is not an act of weakness, or romanticism…it is that of a woman claiming her liberty, her strength…and her self…one last time.

Like Antigone (the first and greatest female tragic hero who also used her death as a means of defying male authority) and Edna, Mrs. Mallard's death is her only freedom left, the freedom from life.