Wow, that's really tough Michael. I've been in a similar situation where I had a job that I strongly disliked going into each day and I considered on several occasions just stopping. I didn't have children to support, so it actually was somewhat of an option, even if it may not have been the best course. The job paid really well for the area though (and for my education level) so I was reluctant to let it go. In my case, I was able to go to the manager of my division and propose a new position that I actually would enjoy. That's a fairly rare situation to have though, and it sounds like that may not be an option for you. If you're looking for advice, there are two things I'd recommend.
First, the easiest time to find a job is when you already have one. There's so much power in going into a job interview when you already have a job. You don't like the way things look? You don't like the interviewers? Salary too low? No problem. Thank them for your time and go get lunch with your wife. I don't say this to mean that you should stick with this job that you hate, but instead that if you go ahead and start making your plan for getting out while you can still (barely) tolerate the job, you are going to have more and better options available to you.
Second, you mentioned that you could cut expenses a bit if you were jobless. Now may be a good time to start examining places to cut expenses while you still have a job. This won't help your situation immediately, but a couple of years down the road if you are still at this job you hate or even further down the road if you come to hate your new job, you will have a lot more choices in life if you have cut your expenses and saved/invested that money. Cutting your spending by even 10% and socking those savings away can make a huge difference.
As I've saved and invested more and more, my job stress/angst has consistently decreased. I'm not a point where I can just walk away from work entirely, but I am at a place where I could confidently walk away from a terrible job and know that everything is ok. It's a good feeling to have, and it makes me worry a lot less about almost everything.
Anyhow, I hope that you are able to find something that works better for you. Good luck!