Emails from dead friends

I have an e-mail sitting in my inbox from an acquaintance who died a few months ago. He sent it about two months before his death.

Every time I see the message I think about him and I am afraid that if I erase the message it might erase my memory of him.

I experience this same problem when other friends die and I leave their names in my cell phone. Sometimes I scroll past their numbers with my finger hovering just above the "call" button.

If the numbers are still there, I can play with the idea that their voices are just a phone call away from me.