Were you raised as a witness? I think people are more sentimental about things they are raised with. If you never celebrated it in the past then maybe that is why you aren't into it. I enjoy the music, the colors, food and smells of Christmas but not the shopping frenzy that goes on at this time of the year.
Then again my whole theory could be wrong because I don't think anyone is sentimental about celebrating (I use the term lightly) the memorial.