I became PBC shortly after getting married the first time. My Nmom ruined my wedding, and she was very successful (my friends refer to it as "MagPi11's terrible day). I eventually had to get a restraining order because my Nmom threatened to kill me. I cut ties with my Nmom, dad (abusive just not N) and my 3 siblings. I am now close with 2/3 of my siblings but it was not always so (took us over 5 years to rekindle our relationship).
The GC brother I still have not contacted. My other 2 siblings took a bit longer to get away from the abuse and were brainwashed into thinking I was the one in the wrong about the whole situation. Now, many years later, me and my 2 siblings are a family of our own and none of us speak to our parents or GC brother.
When I left my family and became separated from my ex husband (marriage lasted less than a year), it all happened within the same year. That Christmas, I spent it alone. Luckily I had friends who knew of the situation and were very comforting to me. On Xmas eve, one of my friends brought me over supper and dessert his grandma made. I had friends invite me over to their houses for Xmas but I chose to be alone. I was very depressed and didn't want to be a downer at their family Xmas'.
I was so lonely on Xmas day. I kept thinking about all that would've been happening throughout the day. "Oh it's 8 am, they're probably opening gifts", "7 pm having Xmas supper".
I got passed that and moved on. After that point in my life I would go to friend's family holidays or enjoy holidays with my extended family. I am engaged now and I am a part my future husband's family; I either spend time with his family or my newly PBC siblings, or both.
I am so happy to admit that my Nmom, my brother (the golden child, who is also a N) and my abusive/absent father will not be at my wedding. However, I will have friends and extended family who will attend. Even if there are not a lot of people attending my wedding on my side, I would never want my Nmom at my wedding again. I know it would turn into a nightmare all over again.
Trust me, as time goes on you will build a new life for yourself. I remember having the same feelings as you did. Time was one of the main factors in helping me heal/forget. But also friends/other family members and SO help as well. I wish you all the best on your journey ahead. It's not easy being PBC, but it's harder to be in the situation you were in prior.