Sorry to hear about your loss. Losing a dog can be rough. I've lost a couple over the years.
My current dog is getting up there in age as well. I know I'll have to cope with the loss eventually. She almost died a few years ago due to a really bad sickness, but she didn't. After she recovered, it really made me appreciate her that much more. Not a day goes by I don't play with her or show her my affection. She knows I love her and when it's her time to go, she will go happy knowing she was loved and cared for the best I could.
I suggest getting another dog, especially a puppy. It REALLY does help to ease the pain. You'll have a new little ball of fur to play with, and love, and it helps takes your mind off your loss. Trust me and the others who have suggested it. It works.