The narrator portrays Mathilde as a kind and loving person who is trapped in a life that does not meet her expectations. She is not inherently materialistic, but she becomes obsessed with the necklace because it represents the luxurious lifestyle that she believes she deserves. The narrator also highlights Mathilde's vulnerability and naivety, as she is easily swayed by her friend's luxurious possessions and does not consider the consequences of her actions.
Despite her flaws, the narrator ultimately paints a sympathetic picture of Mathilde. She is a relatable character who is struggling to find her place in the world, and her actions are understandable, if not always wise. The narrator's sympathy for Mathilde helps to create a sense of tragedy in the story, as the reader feels empathy for her character even as she makes poor choices.