I really love this song too.
I think the last verse is the grandfather giving Lem advice on his recent relationship. And I do think the reference of "moments of our lives cradled" is a reference to God or whatever higher being there might be. He's clearly thinking about when he cradled the snails. But notice that he puts the snails down in some random place, possibly far from where the snail lives. Similarly do we often get disoriented by changes in our lives.
And furthermore - he "drained" her defenses. So he didn't cradle her softly enough.
I really love this song too. I think the last verse is the grandfather giving Lem advice on his recent relationship. And I do think the reference of "moments of our lives cradled" is a reference to God or whatever higher being there might be. He's clearly thinking about when he cradled the snails. But notice that he puts the snails down in some random place, possibly far from where the snail lives. Similarly do we often get disoriented by changes in our lives. And furthermore - he "drained" her defenses. So he didn't cradle her softly enough.