You know how they say, "Don't sweat the small stuff?" Well, it's even more important, "Not to sweat the BIG stuff." The more important something seems to be, the more important it is for you to act upon it with calm. Astronauts seems to have a sense of calm and good humor even during life threatening situations. You want your doctor to be calm. Allowing things to ruffle you does not help; stress may only trigger relapse. But you intuitively know this. The hard part is staying calm during stress.
Take the four steps to stress reduction: (1) Accept what is going on and don’t try to escape or fight when “flight or fight” is useless. (2) Assess the importance of the situation. Sometimes a need may be threatened, but sometimes we magnify situations such that what we think is a need may really only be a want. (3) Breathe slowly. Control your breath through the inhale and exhale, and connect to a Higher Power. This Higher Power could be God, a trusted friend, a Sponsor, a spouse, a parent, a therapist, a minister, or a combination of many things, etc., and (4) fix your stress by detaching emotionally and look at what you have to do as "tasks" like any other non-emotionally charged event.