You're absolutely right, and under better circumstances it'd be an excellent argument to make. Thing is, I'd rather have died years ago and if my heart were to give out today, it'd be doing me a big favor. As for the psychological benefits, they're pretty slim on a daily basis even if I manage to stick my schedule. I'm sure I'd feel better about myself if I were toned... but I have little to no confidence I can pull that off with my **** genes, and when all I have to work with is my own body weight. And come to think of it, being ripped wouldn't really help me in any concrete way either unless I take up manual labor or sports or something.
Sorry you're feeling like you want to die. I guess the way I think of it is, unless I kill myself, I have decades more I have to live. The thought of going into old age and being so weak and helpless that I lose all independence is terrifying to me and a big motivator. You don't have to get ripped or even toned. Bodyweight exercises are good as is walking every day and throwing in some runs. Something is always better than nothing.