Yes hellsbells is right re: food. You'll start to feel really crap if you don't eat a little something to keep your electrolytes balanced. It can be anything, the rule book doesn't apply. If you have nothing in and can't bear the thought of going out can you order a little shop online via Tesco's et al?
Tinned soup is an excellent suggestion. My survival diet was rich tea biscuits, with yorkshire tea and jacobs crackers with cheese. All sprinkled with a goodly dollop of salty tears. I remember eating in stages, one bite, go away sleep and cry, come back have another two bites.
I looked great that summer ha! And I felt like crap. Worst summer of my life!
With regards to crying: It's really important to let it it all just wash out. It's your body's coping mechanism. Don't worry about whether you should stop by now. It will gradually lessen as hells says. I swear I cried so much those first few weeks, I could have singled handedly provided Thames Water with enough backup in its reservoirs to reverse the hosepipe ban that summer.
So let it all out and a big well done for resisting the urge to call him. That shows how strong you are.
Snowwhiteandrosered I am 
that you were abandoned during a nervous breakdown! What a horrible thing to do to somebody. I am full of awe to see how you've picked yourself up. You strong lady!
GeorgeP So sorry for what you're going through
But you'll find lots of support on MN when you're ready to talk, just hang in there.