Need to find Lewis Quote

Friends:
I am trying very hard to locate a quote by C. S. Lewis, in which he expressed
the view that we must choose to risk loving, or, else, be assured of being
alone.
It may have come from "Surprised by Joy," but I'm not certain of this.
Can anyone help me find the this quote?
Thank you, very much.
Jerry Moore
e-mail: alanbylane DeleteThis @aol.com