As you probably know big life changes can be particularly stressful. A lot of young people move back in with their parents before they find work. I know when I graduated college the majority of my friends did move home. And it is true, you may not find work in your field right away but that does not mean you won't find work. And graduate school has different requirements than undergrad. They look for more than just GPA and GRE scores. You may find you are more attractive to them after having been in the real world a bit.

I know this does not address your primary concern. I am sorry you are feeling this low and I really hope this helps somehow.