A rose for valentine's day

So much has been said on the subject, that I can resort to lines almost at random

"You'll never know if you don't know now..."
"You do something to me..."
"A nightingale sang...
"Auf Wiederseh'n..."


Obviously I could go on almost indefinitely, and that's just what I was listening to in the car on the way up to Atlanta. Happy Lover's day.