Sorry have just realised I name-changed halfway through this thread! I am kinkerfuffle. It just took too long to type.
I too am horrible to my husband when down. I take it all out on him and he's so good to me, he just seems to take it. He knows I'm really bothered about other things and just use him as a punch bag but that doesn't make it ok! I feel awful for it, but he understands, just as I'm sure your dh understands too.
You're not effed up! You sound like everything has just suddenly gotten on top of you and is getting you down. It's never easy, and as the nights draw in it just seems to get harder. I know what it's like to have an absent husband too! DH used to work away quite a lot and I'd find the long days just with the kids hard work.
Talk to DH, reassure yourself that you're doing just fine (cos you are).
It doesn't matter if it is expected for your family to run to the hills, it still bloody hurts if they do! You could've done with support and you didn't get it. The fact that you don't blame them and you understand why means that you are a GOOD person!
Your DH sounds as though he really loves you. Look out for each other. Try to do something nice for him when you're feeling calm, and apologise for being a cow. Let him know that his patience has been noticed and appreciated. You'll be ok.
Let me know how you are. Sorry it took so long to reply to you.