Why is Madame Liosel disconnected at the beginning of the story?

Madame Liosel yearns for a life of luxury and wealth. She feels that she belongs in the upper class yet must live the life of a commoner hence her feelings of disconnect with her life. When she is invited to a fancy party, she borrows a necklace from her wealthy friend Madame Forestier because she refuses to go to a party without expensive jewels and a beautiful gown.