I think you did the right thing. I'm not going to repeat what others have already said, because they said it better than I could. I will say this. The one person it sounds like that will need you on Christmas is your Grandfather. Have him over for dinner, or go to his house, and spend time with him. Regardless of all the other things and people, he's going to need someone around. I remember my Grandfathers first Xmas without my Grandmother, he was grouchy and tired and complained, but in the end it was obvious that he needed us there.