Well I'm not sure if I'd ever feel that way unless I had no joy. I'd wonder why the hell do anything if I'm gonna die anyway if I had nothing to live for. But I get out of bed in the morning to hang out with my friends, take care of responsibilities, etc. some shit is bad but thats part of life(Can't have the good without the bad) Kind of a wild guess but maybe you haven't ever found your purpose in life? If you find your purpose as more than just existing then you'll strive to become whatever it is you're supposed to be/do and have a reason to live. If your just living to live you should find your purpose in life!