You know theres maybe 1 or 2 people in this world who cant understand why people can love a pet more than themselves, but a lot of people do understand.
No one here is gonna bash you for loving the fvck out of your dog or even being closer to it than your own wife (that not a joke my own father and mother give their dogs more attention than each other). So you have every right to be sad, just think if you died first how sad your pup would be and whether or not you would want it to go by the front door everyday cry and waiting for you to come home.
IT SUCKS. But you need to muster that little bit of truth and knowledge that NOONE, ESPECIALLY your pup wants you to suffer, in fact they want the complete opposite.
Dont try to hard to forget because its not easy, but ALSO dont try too hard to not forget, because your dog definitely wouldnt want it that way.
And when I say 'forget' I dont really mean forget, people never forget things they loved. When I say forget I mean FORGET BEING HARD ON YOURSELF.
Gluck!! And remember things always get better.