I'm not going to give christmas gifts this year
Why aren't you giving out Christmas gifts?
I don't think people should give presents to other people for arbitrary reasons.
While it is perfectly reasonable that you don't want to celebrate Christmas, you need to make sure our friends and family know your stance. This will ensure that they do not give you gifts with the expectation to receive a gift from you.
I've decided not to celebrate christmas this year. I want to make others aware of the fact that I don't celebrate Christmas. I will also hurt their feelings.
Your choice to not celebrate any holiday is fine. However, be sure to explain how you feel about it clearly and respectfully to your friends and family so that they understand your decision.