How we cite our quotes:
She was one of those pretty and charming girls, born by a blunder of destiny in a family of employees. She had no dowry, no expectations, no means of being known, understood, loved, married by a man rich and distinguished; and she let them make a match for her with a little clerk in the Department of Education. (1)
The opening line of the story makes it sound as if Mathilde is almost fated to be unhappy. It's only chance – being born into one family and not another – that prevents her from living the kind of life she so wants to lead. Naturally, she's attractive and charming, and if she were born into a rich family rather than an average one, she'd have the life she wanted. Something that's a result of luck – what family she's born into – becomes a fate fore her, because it restricts the possibilities for the rest of her life.
She suffered intensely, feeling herself born for every delicacy and every luxury. She suffered from the poverty of her dwelling, from the worn walls, the abraded chairs, the ugliness of the stuffs. All these things, which another woman of her caste would not even have noticed, tortured her and made her indignant. The sight of the little girl from Brittany who did her humble housework awoke in her desolated regrets and distracted dreams. (3)
Mathilde is unhappy locked up in her house, just being there makes her suffer. She finds it oppressive. Her only method of coping with it is to live in a dream world. The question is, does Mathilde just suffer because she's excessively greedy? Or does she suffer because her life is boring and meaningless?
And she wept all day long, from chagrin, from regret, from despair, and from distress. (6)
In case you needed any additional proof that Mathilde is miserable, she spends all day crying. Her life has essentially nothing enjoyable in it.