Quite interesting. I believe a lot of us in the Software Industry are suffering from this but without acknowledging it and/or forced to ignore it due to circumstances/social factors/rat race. I am quite fascinated by the psychology behind "burnout" (maybe suffering from it myself) because it not natural for us to be in a constant state of stress arising from problem solving as is demanded by the industry. The lack of physical activity exacerbates the problem and you are caught in a vicious cycle leading to mental/physical breakdown.

Would you mind sharing some details? What exactly happened to push you over the threshold? How was/is your physical health? How exactly is your mood/emotions affecting behaviour? How do you feel before/after?