My mother and father got divorced a year ago and it is really messing with my mind.
Do you always think about this divorce?
During Christmas and my birthday they bring it up, so it's hard for me not to think about it.
If both of you parents are showing up for Christmas and your birthday, it means that they still care about you. It is fine to still be thinking about divorce after it happens, it is a serious event that can bother you for a long time.
Yeah that might have been true a few years ago. They don't even bother to call now.
It can take as long as you need to get over something like this, as it seems to be a very serious thing. Divorce affects even the people not divorced, meaning you, in very serious ways. One day you will feel better about it.