In Guy de Maupassant's short story "The Necklace," Madame Loisel is ungrateful because she is never satisfied with what she has. She is forever wishing for a more, believing she has been shortchanged by life. She never shows appreciation for what she has, including a hard-working husband who tries his best to make her happy.
While Madame Loisel is a pretty young woman, she was born into a family without money or connections. Without a dowry or prospects...
...she let herself be married to a little clerk of the Ministry of Public Instruction.
Even this reference makes her seem ungrateful, as if despite a similar position in society, she allows herself to marry beneath the station she feels entitled to. During this time period, it is more socially acceptable to be married than be a spinster. This is one way in which she should be pleased with her life. However, she acts as if she "had fallen from a higher station."
Mathilde suffered ceaselessly, feeling herself born to enjoy all the delicacies and luxuries others enjoyed.
She is obsessed with the lifestyle she wishes she had— the parties she dreams of attending and the food and flattery accompanying such occasions:
...she thought of dainty dinners, of shining silverware, of tapestry that peopled the walls with ancient personages and with strange birds flying in the midst of a fairy forest; and she thought of delicious dishes served on marvellous plates and of the whispered gallantries to which you listen with a sphinxlike smile while you are eating the pink meat of a trout or the wings of a quail.
This is a young woman who is not satisfied with her lot in life. She is an egocentric person who wants to be sought after and thought to be charming. She is only interested in herself.
Madame Loisel's husband comes home one evening with a surprise. It is obvious that he is aware of her overall displeasure with everything about her life, even though he cares a great deal for her and does his best to provide for her. On this occasion, he has been able, not without difficulty, to procure for them a coveted invitation to a special ball.
Instead of being delighted, as her husband had hoped, she threw the invitation on the table crossly, muttering:
"What do you wish me to do with that?"
The story mentions that in thinking about how much a suitable gown would cost, such an amount would elicit a "frightened response" from her husband. We can infer by this that he does not make a great deal of money and such a cost would bring to his mind how easily one could become destitute. He is distracted by her weeping. He reacts to her behavior with "despair." It is clear that her husband wants to bring her joy, but she has no thought of anything but her own desires.
In the face of a man who works hard to make a comfortable life for his wife, it is hard to see Madame Loisel as anything but ungrateful. While he wants to do things that will delight his wife, she acts like a spoiled child, showing neither appreciation for her husband's concerns for her nor thankfulness for his heartfelt wish to please her.