Does the stress bleed over to your non-working hours? What is it exactly that is causing the stress, is it time constraints, toxic co-workers, ect? If you pinpoint what the cause of stress is then maybe you can begin to reduce it.
I can understand that reluctance to quit because you feel lucky that you are able to save all of your salary and still spend time with your kids. For me it's really a simple decision, since I am the only working spouse and I don't want to go on welfare, I suck it up. But I do try to reduce the stress my job causes me, by taking regular breaks and mental health days, not letting little things upset me, ect. I try to focus on the aspects of the job that I enjoy and the things that are meaningful to me.