Things are so tough for people right now.
I've been a single, full-time working mother since my divorce 15 years ago. It is definitely hard to shoulder all the responsibilities for supporting a family.
We've had our ups and our downs, but one thing that really helped me was allowing myself to believe that things do happen for a reason. We may not always understand the reason or be able to see it when we are in the thick of things. But, we just have to keep moving forward.
There have been jobs that I was certain I would just jump off a bridge if I didn't get. They seemed so perfect with great pay and benefits. Each time I was devastated for not getting the job, about a week later, I got an even better one. I wasn't meant to have the ones I "thought" I needed so badly.
This can feel like a really devastating situation for you and your family, but hopefully you can encourage your husband to keep his head up. For whatever reason, he wasn't meant to stay where he's at and I believe it's because where he's supposed to be just hasn't presented itself yet. But, it will. And, he may find that he's much happier in the long run.
It's incredibly stressful to bear the weight of financial responsibility for a family by yourself. You're just going to have to be as supportive as possible.
If your kids are in school, you could always try to get a part-time job while the kids are out of the house to help bring in a little money.
Hang in there. Things will work out.
Best wishes.