When I saw this prompt, my mind completely blanked on what song lyric or lyrics made an impression to me.  Then, as I was reading what everyone else had put and it hit home like truth to me.

From the musical RENT (written by Jonathan Larsen).

There's only us, there's only this
Forget regret, or life is your's to miss
No other path, no other way
No day but today.


Life is fragile.  Any day could really be our last.   Enjoy today.