Monica - so sorry for your pain and loss. Although I am not yet divorced (in process of filing), I can empathize with so much of what you wrote - the deep saddness, the holiday season, the OP, and the shock that we are not together anymore.
I am not sure if I can say anything that could ease your pain or be a cure, but please know there are others like you in similar situations. I hope you have a better day today.
Me: 48 Ex-W: 45 M: Nov '96, together since Oct 93 Bomb: on 10-yr anni - Nov '06 OM Separated: mid-Feb '07 Divorced mid-July '08 One daughter - 28 XW living w/OM