Madam Loisel was married to a Clerk in the Ministry of Education
The couple gets invited to a ball and she got upset and didn't want to go to it because she didn't have a dress to wear
The two compromise and she gets a new dress, but then she doesn't have jewelry. She asks her friend Madam Forestier for some jewelry and is allowed to borrow a diamond necklace
...and that's where I've been and doing all this time
Madam Loisel goes to the ball with her husband and on their way home she loses the necklace. He spends some time looking for it but they end up replacing it by taking out loans
What? How? Did you have it at the ball?
Together they spend 10 years working to pay the loans off and to pay people back. The had to move into an attic and get several jobs
After all the money was payed off she goes to the docks to relax and sees Madam Forestier. She decided to approach her and tell her the whole story. Madam Forestier then told her that the original necklace had fake diamonds in it which they replaced with a necklace that had real diamonds.
Oh goodness, dear, The diamond was a fake and made of glass