This is a really well written post!
I lost my dad to cancer in 1984. He was 55 years old when he died. I am now 8 years older than he got to be. It was a long time ago, but I still feel it now and then. Time helps lessen the pain of loss, but all the memories remain with you. It's really good that you have that picture to remember him by when he was still healthy, that's the best way to remember him.