Oh, Iron, I am so sorry for your loss.
Having lost three dogs over the past three years, I know what you are going through. Naura died unexpectedly from a heart problem when she was just 10. She had been energetic and out running with my husband a few days before, so we had no warning. Then a puppy we had for just a couple of months died from unknown cause (vet tests showed nothing when I took her in), and then the one after that, we had for a year and she died from a rattle snake bite. It still makes me cry if I allow myself to dwell on them too much, which I am prone to do, wondering if I could have done something differently to help them.
I have had comfort by being able to see them in dreams. Maybe you'll be able to see your sweet friend that way, too.
We do have another girl now, another sweet lab mix named Lena. But the others are always in our hearts and memories.