The first sentence states that she "was afflicted with heart trouble" and because of this, shocking news was delivered very carefully. That foreshadows the actual physical event at the end. Then, the very first action that Mrs. Mallard performs is one that Chopin describes as unusual for most women: "She did not hear the story as many women have heard the same, with a paralyzed inability to accept its significance. She wept at once, with sudden, wild abandonment". This characterization emphasizes her unique stance on grieving, making her later reaction less harsh.
Then, as she sits in the chair, Chopin describes her face as "calm..whose lines bespoke repression and even a certain strength." This clues us into the fact that she has been repressed, and is a strong woman, so her happiness at being "free" is foreshadowed there. We later get her viewpoint of what marriage had been for her: "There would be no powerful will bending hers in that blind persistence with which men and women believe they have a right to impose a private will upon a fellow-creature." This description of her viewpoint helps us to understand why, after feeling elated freedom, she would be so shocked and disappointed when her husband was actually alive.
The ending is shocking and ironic, yes, but if you look closely, there are clues throughout the story that can help you to understand it better.
The ending of the story is certainly an effective climax to the story in my opinion. The reader has been told that Mrs Mallard has heart trouble, and she is treated very carefully when given the news of her husband’s death. Those around her at least see the news as potentially damaging to her health.
Knowing that Mrs. Mallard was afflicted with a heart trouble, great care was taken to break to her as gently as possible the news of her husband's death.
Louise withdraws to her room after the news is given, and there is concern from her sister that she should not be alone. She is indeed in the throes of powerful emotion, but of joy and exultation, not intense despair-
She said it over and over under her breath: "free, free, free!"
Louisa had chosen to value her independence more than her status as a wife. Her death as a consequence of ‘the joy that kills’ could be seen by the reader as a blessed release or an eternal punishment. It is ironic that her only escape is in death; if not that of her husband, then her own.
Kate Chopin's short story, The Story of an Hour, ends quite ironically and unexpectedly. Over the course of the story, Mrs. Mallard comes to terms with the fact that her husband, Brently, has died. After "grieving" for a very short period of time, Mrs. Mallard finds herself celebrating in the fact that she is now free from his oppressive nature/behavior.
Upon deciding that she is okay, Mrs. Mallard exists her bedroom like a goddess. As she comes to the end of the steps, Brently enters the house. She immediately dies.
The characterization of Mrs. Mallard, up to her death, shoe her as being a very strong woman. Ultimately, she has been able to survive with her husband this long. Unfortunately, upon Brently's appearance, she (having lowered her walls) finds herself unable to take it any longer.
Therefore, some could suggest that her death is justifiable--she could simply not live another day with him. Others may suggest that the minute she felt free, Brently (once again) destroyed her dreams.
This would, at least in part, be a matter of opinion, and opinions could easily differ.
If Chopin has a weakness, it's that she's a bit didactic, or preachy. She has an agenda when she writes fiction. An agenda is entirely appropriate for an essay, but not usually for fiction. Sophisticated fiction usually raises difficult questions and doesn't pretend to have easy answers. Chopin somewhat avoids this, however, by making the husband blameless, or mostly blameless. Her husband seems to be a good man and treats her well. Chopin's problem is with the institution of marriage in a male-dominated society. She is not husband bashing, in other words.
The question of the surprise ending, as it relates to Mrs. Mallard, deals mainly with two details revealed earlier in the story: her heart condition and her excitement over being free.
First, because she has a serious heart condition, a heart attack is not out of a question and is causal--there's a cause, it seems fairly legitimate. Others in the story worry about her having a heart attack when she finds out her husband is dead, so it is a legitimate concern.
Her excitement is also clearly established. She is ecstatic. Though the story is even shorter than the "hour" of the title, her feelings of freedom are thoroughly established.
Thus, her heart condition and excitement would seem to make her fatal attack when her freedom is taken away unexpectedly legitimate.
Another issue is whether or not her husband not being in the accident and arriving at the home is legitimate. But that is another issue, and you asked only about the characterization of Mrs. Mallard.
I think that it is in this arena where Chopin makes her greatest statement about what it means to be a woman through her characterization of Louise. She depicts Louise to go through the entire range of the components that are involved in being "a woman" and does so in a very convincing manner. When Louise hears of her husband's death, she expresses sadness and regret, as most would when hearing about the loss of a spouse. Her ascent up the stairs and into the room, a "room of her own" as Woolf might say, reveals another characterization of her and this is steeped in her own sense of self. Louise is able to express her own identity, her own wishes, and find her own voice. This depiction shows Louise as a person who seeks to transform what is into what should be. The ending undercuts this sense of hope and optimism, and it is here where one can see Chopin's full grasp of the situation. On one hand, Chopin's statement through Louise's death indicates that women have a great deal of inertia to battle through, as Louise is hit with the realization that her dreams will never materialize as long as she is seen as wife first, woman second. At the same time, the fact that Louise has engaged in such dreams and that Chopin has characterized her in such a manner to actually show that there might be a tension that exists between wife and woman helps to bring to light the problems within such a social setting. It is this duality, one that reflect social conditions as what they are while simultaneously presenting a vision of what they can or should be, that is where Chopin's greatness lies and why the climax is so appropriate.
Chopin's characterization of Louise Mallard in "The Story of an Hour" does justify the story's unexpected and ironic climax. At the beginning of the story, Mrs. Mallard is upset over Brently's death; however, this soon gives way to her realization of the freedom that she will have because her husband is dead. When Mrs. Mallard first enters her bedroom, an armchair is already facing the window which suggests that Mrs. Mallard often sits and gazes out of her window. Her dreams of freedom as symbolized by the carefree descriptions of the spring lead the reader to understand that marriage has been an institution of constraint for Mrs. Mallard. She even gives the notion that when married, she felt that life was going to be long and hard to bear. Because the reader understands the relief that Mrs. Mallard feels as a result of her new freedom, the end of the story is shocking, unexpected, and of course ironic when the others assume that she died because she was happy. Readers know that her feelings were quite the opposite.