Do you think hard work changed Mathilde's character?

At the beginning of the short story, Mathilde Loisel is depicted as a superficial woman, who desperately desires to be part of the upperclass and enjoy a luxurious life. Her lack of material wealth and lower-class status leaves her miserable as she naively believes that worldly possessions will make her happy. Mathilde's attitude instantly changes when Madame Forestier allows her to borrow a presumably expensive necklace to wear at a prestigious ball with her husband. Mathilde thoroughly enjoys the ball and feels triumphant in her beauty. Unfortunately, Mathilde loses Madame Forestier's necklace and she is forced to spend her inheritance and toil for ten years in order to pay the thirty-six thousand francs to buy a genuine replica of the lost necklace. Mathilde prematurely ages over the years because of her hard manual labor but still finds time to daydream about the lovely ball when she wore the fancy necklace. Mathilde's daydreams indicate that she still values material objects and has not experienced a change in character over the years. She remains superficial and miserable as she toils to pay off the genuine necklace for Madame Forestier. Mathilde's values and character remains the same throughout the short story and she does not learn that material wealth cannot bring happiness.

It certainly changes her outward appearance. When Madame Forestier catches up with her years later, she doesn't recognize Mathilde. Mathilde has been thoroughly worn out and prematurely aged as the result of all the hard toil she's had to do to pay off the loans she took out to buy a replacement necklace.
But there doesn't seem to be much evidence that her character has changed all that much. When her husband's out at work, she often sits by the window wistfully recalling that magical night at the Education Ministry ball when all eyes were upon her. She reflects on what might have been and what a great life she might have had if only she hadn't lost that necklace. This indicates that Mathilde, despite a decade of ceaseless toil, still hasn't learned her lesson. She's still living in a fantasy world, still unable and unwilling to come to terms with reality. It is this unhealthy attitude to life that got her and her husband into such deep trouble in the first place.