Firstly, I am sorry for your loss. Secondly, life goes on for everyone except for those who experience the loss. For us, we wonder how everyone else just continues on as if nothing happened? People forget very quickly that you have just suffered a loss because of all their own responsibilities and issues. My own good friends keep inviting me out for dinner and a movie and I have to keep reminding them I am in aveilus for my mother and can’t go. This is my own good friends how do you expect a Rabbi or gabbai to keep in mind what may or may not be going on in the heart or mind of a niftar’s grandchild.
On the other hand, if you need to speak to the Rav and tell him that you are still suffering and would love to talk to him about it or about any stories he can relate about your grandparents I am sure that he would gladly oblige and be there for you. A Rav’s day, week, months are filled with obligations happy and sad not only to his own kehilah but to the community in general. That is a huge burden on one’s shoulders. Please do not hold this against him, just ask for some of his time and I am sure he will make the time you need.