Maybe not all girls, but many girls are brought up to believe that a man should be a provider. The level he feels this responsibility, his drive to succeed is part of his character. When most women are looking for a potential mate, they consider how well will he provide for us and our future children? It is not that we can't support ourselves, but it is an ingrained idea that it is his responsibility.
What happens when he has lost his job? We see many men where this has happened, and they are depressed because they believe that it is now a character flaw. The woman does not see him as attractive, because he is no longer the provider. The fighting begins. They fight over money, over whatever, but the reality is that he is not filling the role of provider. He feels like less of a man, and she reminds him of it with her nagging.
I am not saying this is true for all couples. It is just an observation and an invitation to discussion. Is this really fair to a man? How does this level of responsibility as a man feel? As a woman, do you find a man less attractive if he is not a good provider? If you have experienced losing a job or a career as a couple, how did you handle it?