Mathilde's husband had 18,000 francs in savings--one-half of what they needed to purchase an identical diamond necklace as the one they had lost--but the couple had to raise the rest of the money themselves. Monsieur Loisel borrowed the remainder, risking his future in order to pay off the debt and avoid the possibility of being imprisoned for theft.
He did borrow, asking a thousand francs of one, five hundred of another, five louis here, three louis there. He gave notes, took up ruinous obligations, dealt with usurers and all the race of lenders. He compromised all the rest of his life, risked signing a note without even knowing whether he could meet it...
When he had borrowed the remaining 18,000 francs, he sent his wife with the money to repay Madame Forestier, who chastized Mathilde, telling her
"You should have returned it earlier."
The couple then spent the next 10 years working additional jobs--he worked evenings and even late into the night, and she fired her maid and did all of the housework herself--saving every penny they could in order to pay the husband's promisory notes.