I think it is just him reassuring someone who is dying that the times they had together will make (her?) immortal in a sense and that you can never really die because you've touched so many people that (cheesy coming up ->) a piece of you will always be with them even after death, you may not be alive literally but your past actions will keep you alive in other peoples hearts.. But the person telling her all this isn't even sure if he can live with just memories.
I think it is just him reassuring someone who is dying that the times they had together will make (her?) immortal in a sense and that you can never really die because you've touched so many people that (cheesy coming up ->) a piece of you will always be with them even after death, you may not be alive literally but your past actions will keep you alive in other peoples hearts.. But the person telling her all this isn't even sure if he can live with just memories.