ok. This will be hard for you to accept....it was for me. I used to compete in triathalons, mountain bike, downhill ski, play tennis and racquet ball. I was an exercise maniac.
On the weekends, I used to exercise literally all day long. Bike to gym, lift weights, play racquet ball after lifting weights, bike home. Then go play tennis. I felt like a machine like you described and there is a reason for that (explained)
Excessive exercise is one of the causes of stress that resulted in your condition. Anything more than gentle exercise is a source of stress. It is not just mental activities that cause stress.
Just like I had to finally accept, you need to move to more gentle forms of exercise. Your days of doing ½ marathons may be over. You just won’t be able to calm your nervous system down with the high level of stimulation that happens with intense exercise.