I think he was afraid to let this love continue in case it changed, or left....he wanted it to be for eternity and now it couldn't change. Don't some poets or people say 'I love you to death'! He was so insecure in himself .... now he can NOW he was loved with an unchanging love.

Maybe not as deep as Freud and wishing to be back inside Mother and all that stuff... I've know someone love a kitten so much she squashed it to death. (and she was ten.)