"I have measured out my life with coffee spoons." What is the author saying about the way that Prufrock has lived and is living his life?

I believe that the reference to coffee spoons means that Prufrock is living his life in carefully measured doses. He is not a man prone to extremes or one who would do anything out of the ordinary or unexpected; spontaniety is not his way of life.

Yes, coffee spoons can refer to the fact that he uses coffee spoons at all of the teas he has been to, but moreso it creates an image of one who is precise and exact--Prufrock would never just dump the sugar into his tea! Each and every decision he makes is carefully weighed and measured.