Things are always falling away. They will continue to do so. You can come to understand that the really important things are there. The sky is there. The ocean is there.
Life is there.
Those things will not slip through your fingers. The only things that will slip through your fingers are your desires and your preconceptions. What is true will just remain. It's a noble endeavor that we do together, sitting zazen, examining our interwoven lives. We do it with all our heart and mind.