I'm going to be honest with you, my father had gone through a similar situation.
Not so much your exact situation, but a similar root to the problem.
My father works several jobs at once. I mean the man gets two hours of sleep a night. He comes home, and all he wants is food on the table. Unfortunately, due to huge amounts of stress at home, my mother is unable to provide this food for him. She may also have a mental disorder, to be fair, but at the same time, my father only wants dinner and a relaxing environment to come home to.
Several months ago (years, maybe?) I told my father that I had hated him for the way he had treated my family. Honestly, it was based on how he had acted towards me, though later I discovered where my feelings came from. Nonetheless, my words hurt him deeply.
He received no real respect from his son (20), nor two daughters (18 & 6). He began to distance himself from the family, and became extremely angry whenever he came home.
It wasn't so much the fact that he was angry at us, nor hated us, nor that he wanted nothing to do with us. It was just that our home, the people in it, and everything in the house became associated with monstrous amounts of stress, frustration, and an intense lack of happiness. The man was very tired, stressed, irritable, and angry.
It seems to me that you are very, very exhausted with the entire situation. You love your husband, you love your children, but there is an intense frustration involved with nothing going right. This makes you intensely irritable. I don't know what you are associating the nice things your husband does to you with, but it is obviously an irritatnt: perhaps things are just so ridiculously frustrating all around and he, himself, has become associated with this stress? I know you love him, you've made that apparent. But just because you love him doesn't mean that he isn't associated with this pressure and frustration. My father almost left my mother because of all this: it's not too late to remedy the situation.
Your children are being children. I know they are driving you crazy, but odds are you would be able to handle it if the situation wasn't as bad as it was. Children are moderately irritating in normal situations... it's no wonder that you can't really seem to handle them now.
You don't need medicine. I've said this to others... medicine may make you feel a bit better but it won't alleviate the stress you have at home. Honestly, make sure you are just getting enough sleep and getting the vitamins and nutrients you need. That will help you more than anything else right now... this entire situation is surrounded in stress.
The only tips I can give regarding stress are those that you probably already know. Your husband is going to try to find another job, and if determined enough, it shouldn't be a very large problem, despite how bad it looks right now.
Your children are children. You want to keep the relationship between them, it's very apparent. Just do your best to keep your stress with them under control: believe me, having parents under tremendous stress who don't try to take care of it internally doesn't do too much good for the children.
This is all apparent in just how badly you want to run away from it all... the aura in your home probably reeks of stress. Just driving home and waking up in the morning are probably two of your least favorite things of the day. Going to sleep is probably a godsend, and driving anywhere by yourself, whether via shopping, seeing a family member or friend, or whatever it may be, it gives you a satisfaction you can no longer get at home.
I don't know what religion you are, but there are many individuals who find solace in praying to whomever (or whatever) they believe in, seeking spiritual guidance. Forgive me if this statement offends, I know to some it does, but others know what I mean.
Everything will work out, no matter how insane the entire situation seems. We all go through really tough points in life, they break us apart, make us stronger, and always happen for a reason.
Oh, and you don't have depression, I assure you.
Symptoms of Stress - WrongDiagnosis.com
Escapism - Wikipedia, the free encyclopedia
You may be tired of taking care of everyone, but remember, right now, you are your family's pillar of strength. Perhaps, actually, your husband is now, but in regards to your children, they still need you on many levels. Things will get easier... I promise, whatever that may mean to you.
Just remember these things... your emotions are very, very important, as are those of your children. As Choux suggests, you may want to take a vacation... but I would do it with whatever makes you feel more comfortable: being just with your husband, or being with your entire family: some find one more preferable than the other. Either way, do something that makes you happy, but don't run away from your problems, no matter how strongly you feel you should. I could go in to why, but odds are you already know. When you do take your vacation, just make sure that you go after much of this stress is alleviated, and use it to repair the relationships among your family. If you take it when you are still stressed like this (God forbid you take it when your husband still doesn't have a job... it'd never leave your mind), it won't end well.
Know this... while you have been through a lot, there isn't much more that will happen soon. If you can get through all of this, you can certainly get through the rest that is going to come. You may get more and more frustrated with it all, but this will pass.
I hope the information helps.