Boat and Rock - You illustrate both sides of the issue well. At this point, I would not invite W to join our daughter and my dad's family for Thanksgiving. I've been fired and it feels consistent with GAL'ing and detaching. No cake eating as Boat indicates. Let W experience the first holiday in ~20 years w/o a partner and our daughter.
That said, I feel for my daughter who I expect would like to experience at least one more Thanksgiving and Xmas as a "whole" family. That's where the "if it is good for my daughter, it is good for me" comes into play. So, if I put what's best for me personally aside, I can extend an invitation with NO expectations whatsoever.
Or, maybe it is better to rip off the band-aid and also help my daughter move to adjust to the potential future of having divorced parents.