Although there are no literal translations for this, there is a saying in Chinese: "珍惜每一天" ( Zhēnxī měi yītiān ) which is basically the same thing. "Cherish each and every day."
tell him the most wasted thing you shared with him.. i mean the bad memories you had with him and what you learned from it. make sure you say it the way he'll appreciate it.. make your voice so soft...
It is unkown who orginally said that quote but there are many along those lines Including "Live everyday as if it were your last, because one day it will be." J.Shwartz "Live every day as if it were...