> A couple of mental hops and they've now incorrectly associated their peace with the success of their business.

This.

Personally, I find physical activity the best way to combat this. Last year I biked 4,000 miles commuting and on long weekend rides, lost 30lbs and feel super healthy physically and mentally. Now I attack situations in my business and personal life like a big hill climb. I know I am going to get through the pain, I try to embrace the pain because I know if I don't give up I will be stronger because of it.