First Christmas estranged from mom

I know that I'm not the only one but I'm really struggling today. Today marks ten years since my grandmother (the only woman who knew of the abuse) passed away. And it also marks the first ever Christmas without my mother since we went no-contact in June. We are currently low-contact but it's heading towards no-contact again and I can't have her in my life because she is with my abuser and keeps telling me that none of it ever happened. I'm just so sad and want Christmas to go away. I hate that it has to be this way. But for my own mental health I have to do this. My mother keeps delivering presents and trying to send money to me for Christmas. I'm worried I won't be strong enough to keep her blocked tomorrow. Any tips for staying strong and not breaking?