i know how you feel. i just lost both of my grandparents to cancer about two months ago. i know it hurts and that you can't help but feel guilty, but you need to know there is nothing that you could have done. you being his friend probably brought more happiness into his life than you will ever know. and you will always have him in your heart- this i know. your love and support helped him through the tough months and maybe made his illness just a little more bearable. ALWAYS remember that. if you don't, the guilt will never go away and i don't think he would want you to suffer. you and the family will be in my prayers.