How do Madame Loisel's perspective and attitude about life change over the ten years she spent repaying her debt?

Madame Matilda Loisel, the main character in Guy De Maupassant's short story, "The Necklace," is a dynamic character whose attitude and perspective about life goes through changes over the ten years she spent repaying her debt. 

In the beginning of the story, Madame Loisel is obsessed with status and money. She is dissatisfied with her station in life. She was born into a family of low status. She takes a husband who is a lowly clerk, and she is dissatisfied with the modest home she lives in. Following is an example of her desires from the text:

"She suffered endlessly, feeling herself born for every delicacy and luxury. She suffered from the poorness of her house, from its mean walls, worn chairs, and ugly curtains. All these things, of which other women of her class would not even have been aware, tormented and insulted her. The sight of the little Breton girl who came to do the work in her little house aroused heart-broken regrets and hopeless dreams in her mind. She imagined silent antechambers, heavy with Oriental tapestries, lit by torches in lofty bronze sockets, with two tall footmen in knee-breeches sleeping in large arm-chairs, overcome by the heavy warmth of the stove. She imagined vast saloons hung with antique silks, exquisite pieces of furniture supporting priceless ornaments, and small, charming, perfumed rooms, created just for little parties of intimate friends, men who were famous and sought after, whose homage roused every other woman's envious longings."

Madame Loisel's husband tries to make her happy by securing an invitation to an exclusive party, but she is still dissatisfied. She has no fine dress to wear and no jewels. Her husband gives her four hundred francs for a dress and suggests she see her childhood friend Madame Forestier for some jewels. She borrows a diamond necklace and has the time of her life at the ball. She is charming, admired, and dances well into the night. 

Tragically, she loses Madame Forestier's necklace on the way home. She and her husband are bound by pride and duty and come up with a plan to replace the necklace rather than admit its loss. They buy a look-alike necklace for thirty-four thousand francs, and it takes them ten years to pay off the debt. 

In that ten years, Madame Loisel goes through many changes. Some are physical, and some are changes in her character. It seems even her ambitions have changed, and by the end of the story, she seems resigned to her meager lot in life.  

Consider the following quote from the story:

"Madame Loisel came to know the ghastly life of abject poverty. From the very first she played her part heroically. This fearful debt must be paid off. She would pay it. The servant was dismissed. They changed their flat; they took a garret under the roof.

     She came to know the heavy work of the house, the hateful duties of the kitchen. She washed the plates, wearing out her pink nails on the coarse pottery and the bottoms of pans. She washed the dirty linen, the shirts and dish-cloths, and hung them out to dry on a string; every morning she took the dustbin down into the street and carried up the water, stopping on each landing to get her breath. And, clad like a poor woman, she went to the fruiterer, to the grocer, to the butcher, a basket on her arm, haggling, insulted, fighting for every wretched halfpenny of her money."

Later on, she is described as a strong, hard woman. Her facial beauty is gone, as she has aged so much that her long time friend Madame Forestier doesn't recognize her when she sees her. She gives up on maintaining her physical appearance, which previously had been so important to her. Even her voice has changed, and she is described as speaking in a shrill voice. 

When she confronts her friend, she is unencumbered by the desire to impress. She is no longer concerned with how she looks or how people perceive her. Her friend is shocked at her appearance. When she explains the story of the replacement necklace, Madame Forestier is shocked. She divulges that the necklace she loaned Matilda was not made of genuine diamonds. This is how the story ends, leaving the reader to make inferences about Matilda's reaction to this news.