I empathize, but it is not consolation for those who have to be the brunt of his problem.
He needs to give himself a swift kick in the ass and start running every day, kick the addiction, to switch his life back on. Well never give other people advice. He just probably doesn't realize I am not a callous person. But again as addiction illness goes, it is nearly impossible for the patient to be objective about the internal problem and its outward effects.
(I fight every day against a chronic illness and give all my effort. At least his is curable with effort. Mine not certain. He should realize how lucky he is and seize the opportunity on health that others don't have.)