What you've described is the human condition--our reconciliation of a relatively short, finite existence with the unceasing passage of time. Time doesn't really exist, it just affects us, so effectively it does exist.
What you're feeling has lead to civilization, essentially. I think the finite nature of a human life isn't an inherent property of the concept of humanity, but I think a lot of the ideals thats we use to define humanity are born from this finite nature (respect for life, respect for each other etc., the idea of "respect"). Separately, I think the term "respect" has been taken over by game theroretic ways of thinking, which I find disappointing. Such is life, I suppose.
What you're feeling has lead to civilization, essentially. I think the finite nature of a human life isn't an inherent property of the concept of humanity, but I think a lot of the ideals thats we use to define humanity are born from this finite nature (respect for life, respect for each other etc., the idea of "respect"). Separately, I think the term "respect" has been taken over by game theroretic ways of thinking, which I find disappointing. Such is life, I suppose.