I am setting here now with wet eyes. I also lost my (son) (black lab) Maxtor... which I use his name for my username. He also was 12 years old. It has been two years, and the back yard is so, so, so, so empty. I have a lump in my throat now. It is so very tough to loose a four legged family member. You will have years of heartache. It will be very painful, but as time goes on, things will get better. You will never forget him, but life goes on. We have gone through six dogs in our married lifetime (no children), and it gets harder ever time you loose one. What would help us when we were younger was to go out and get another dog as soon as we could to give the new dog our love, which would give us less time for sorrow. My wife and I are at a time in our life that we want to do some traveling, so we are delaying getting our next buddy, until we finish some traveling. We are going on a 10,000 mile trip, then Australia, New Zeland, and Alaska. Traveling is not the best for a young pup. After that we will get another buddy.
You have my deepest sympathy for your loss.
I can not fathom how much pain it would be to loose a child, nowing how painful it is to loose one's dog.