It's ok to hurt. It's ok to hurt a lot. It doesn't mean anything is wrong, just that you are paying attention. The sadness and loss is real and valid, but it won't kill you, drinking will. You haven't failed, just put the alcohol aside and tell us about it, we can help you do something worthwhile with the pain, the booze wont.
sharing the memories and pain with us will honor your father, the bottle won't.
sometimes the hurting/feeling/healing we do at times like this really boost us forward in our sobriety, they aren't automatic setbacks.
I know this for a fact as I am processing tremendous and multiple losses in my life right now as well. Using won't bring any of those things back, it'll only take more from me.
you came to the right place