I don't see that as depressing at all. I find that once you accept that human life and health aren't limitless, it allows you to enjoy every day a lot more than when you think that the days are unlimited. Everything you do and own exists in this time and space which you also temporarily occupy - enjoy it while it lasts, because it will end at some point. It's not depressing, it's more like giving you permission to enjoy life and material things to the fullest while you can.