You define your own meaning of life. Whether you are Atheist, Christian, Muslim, Jew, or whatever, that is still true. If you want to be high literally all the time, go nuts and have fun with it - but please note, it sounds like you don't, not really?
Consider possibly joining a support group, to help you through working that all out, by hearing stories of others who are further ahead on that path than you? Plus you may be surprised that you could be further ahead along it than you thought.
And yeah the world really does seem fucked, but so what? Don't use that as an excuse to give up, if you would rather have more fun standing up on your own two feet. The world may burn (and freeze, and more likely alternate rapidly between both extremes), but you still get to decide what you want to do about it!:-P
Maybe watch the movie Braveheart, as William Wallace (Mel Gibson) gets eviscerated at the end, knowing full well that he could have chosen to avoid it, but instead choosing to value his pride... and freedom. We all die, every single person who has ever lived has died up until now (barring weird freak events like someone time-traveling from the past beyond us into the future:-P), but you get to choose how you want to LIVE.
'cept it comes instead of a home, ability to afford supporting a family, food (at least the kind with proper nutritional support), medical care, and capability to work at merely one job to make ends meet. So... yeah, easy except for that.