I feel like a terrible mother and could use some advice or contructive criticism. PLEASE, nothing mean?

I'm a stay at home mom and babysit 3 children other than my 4 year old daughter 5 days a week. I've recently lost several of the kids because they are just simply growing up and moving on. So, like the rest of the USA, cut down at work. This also affect my daughter who has known nothing but these kids since she was 18 months old. Sometime within the last few weeks she has been having issues sleeping. She screams and fights for HOURS until she finally passes out. For some reason we can't just let her cry(my husband and I) so we sneak in to check on her. She then starts to act very upset, as upset as I've ever seen her, and it keeps going. I feel awful about being angry and losing my temper with her (I don't spank her though) and making whatever she is feeling worse. In my defense, life isn't easy these days and on top of my job issues my husband just lost our only car on Friday because he was driving uninsured. The insurance company was meant to be automatic withdrawing it, had been for years, and stopped. We overlooked it and apparantly our insurance wasn't affective. My husbands wallet with our credit cards, cash (he had just got atm money to pay our energy bill plus some) were all in the car. He thought he had it on him until too late. So in a nutshell, very difficult time. And in our daughter's defense, I know she is feeling all that we're feeling as well. Can anyone give some input. I feel disgraceful for being standoffish and "harsh" in her fragile state. But what if I'm in the same state? Anyone?