brokenwalls, you are definitely not alone in the way that you feel.
Everyone from burger flippers to corporate execs get stressed from time to time. Perhaps different levels and types, but stress nonetheless.
Personally, I walked away from a $60K+/yr job and cashed out my retirement a few years back. The stress there was, for lack of a better term, subliminal. You only noticed it when it was gone. It was stress over what might happen, rather than what actually happened. It got to the point that it felt that my insides were being eaten up by it, so I got out of there before any permanent harm could come of it.
I now make less than half what I used to, struggle financially at times, and the job has its own types of stress, but I feel infinitely better than I did.

The only thing that I can suggest is to get away from things for a bit... take a walk in a park, go fishing, stuff like that. Anything that'll allow you to forget it for a while and recharge. It's what helps me these days.

Wish that I could offer more...