Mathilde Loisel is the protagonist in "The Necklace," by Guy de Maupassant, and all of her troubles in this story are caused by her own pride and discontent. She has a husband who loves her and, even though they are not rich, they are certainly not poor. (We know that because, by the end of the story, they really are poor.) The problem is that she is simply not content with what she has.
In an attempt to give her a little of what she wants, her husband secures an invitation for them to attend a ball. He sacrifices the money he has quietly saved to buy himself something to let her get the dress she wants; however, that is not good enough and she claims she needs jewels. She humbles herself enough to ask an acquaintance, Madame Forestier, if she can borrow a necklace, which she does. The Loisels go to the party and Mathilde is finally content, at least for a short time.
She danced madly, ecstatically, drunk with pleasure, with no thought for anything, in the triumph of her beauty, in the pride of her success, in a cloud of happiness made up of this universal homage and admiration, of the desires she had aroused, of the completeness of a victory so dear to her feminine heart.
Unfortunately, Mathilde loses the necklace at the party, and this is the beginning of her real troubles. If she had not been so prideful and admitted what happened to Madame Forestier, the Loisels would not have had to work for years to pay off the necklace, losing everything they had in the process.
It is her pride which causes all this trouble. If she had been paying attention, Mathilde would have known that the necklace was not made of real jewels. It was not locked in any kind of a special box, Forestier was willing to lend it to her without much persuading, and it was in a box from a fine jeweler but was not sold by him. If she had not been so single-minded about appearing rich to everyone at the party, Madame Loisel would probably not have overlooked these obvious signs; instead she assumes the jewels are real because she needs for them to be real.
Would I have done what Madame Loisel did? No, because fancy clothes, jewelry, and social status do not matter to me. It may have been an uncomfortable thing to have to admit that I lost the necklace, but it would have been the right thing to do and then I would have discovered the necklace was a fake. You will have to decide for yourself if you would have done what Madame Loisel did.
That being said, however, I cannot discount the change for the better which happened to Madame Loisel and her husband because of this experience. Though she looked much older, she was a much nicer and more content person after the experience. As the author says:
What would have happened if she had never lost those jewels? Who knows? Who knows? How strange life is, how fickle! How little is needed to ruin or to save!
I think many readers over the years have asked themselves the same question as yours. In fact, I have often thought that it was foolish for the Loisels to try to find a duplicate of the lost necklace. For one thing, they didn't have the money to pay for a diamond necklace, but how could they be sure they were getting an exact duplicate when they didn't have the original to compare it with? I would have bitten the bullet and confessed that I had lost the necklace, and I think many readers of the past and present would have thought the same thing. What would Madame Forestier have done? Would she have admitted that the necklace was a fake? Probably. But she could have gotten the naive young couple to pay her some forty-thousand francs in installments over a long stretch of years. She knew the necklace was a fake when she let Mathilde borrow it. Would she be willing to admit that she knew it was a fake if Mathilde told her she had lost it? What was a rich woman like Madame Forestier doing with a fake diamond necklace? She moved in high society. Wouldn't she be encountering many men and women who would see that her necklace was made of phony jewels? What would those people think of her? Would they think she was trying to deceive everyone or that she didn't know it wasn't real and that somebody had deceived her? If Madame Forestier is really wealthy, why would she ever wear a fake diamond necklace in public?