Been there done that a couple of times and it seems tougher every time... but you wouldn't take anything for the wonderful memories that you have of your time together. You can't beat the loyalty and dependability of a good companion like you have had. I don't know who came up with the phrase, but truly man's best friend... and such love, loyalty and companionship is truly a blessing from God for sure.
I know your feeling of loss and feel your pain. Peace be with you brother.