Brita01, what is that old saying? I can't remember it word for word, so paraphrasing, "Stress is the overwhelming need to choke the living daylights out of someone and knowing that you can't."
Well, burnout is when you've stuffed the stress so long that it's starting to come out in physical symptoms. If you don't take care of this now, you'll end up on antidepressants and neurotic like the rest of us!

Seriously, though, do what your heart, mind, and body is telling you to do. Get the hell out of there!