Canon compliant up to battle of hogwarts, Ginny and Bill die in the fighting.
With the Weasley family in ruins, Molly extends her family to those that were once or should have been a part of it. For people like Hermione this worked fine, spending every Christmas and birthday with her mother-in-law was a given, and the big group holidays were bittersweet. Sweet in their reminder than life was moving on, in seeing family again, in being together. Bitter for the empty chairs around the table.
For people like Harry or Fleur they were just bitter. The trips to the burrow were the yearly reminder of everything they had lost. As much as they hated going, they knew what it meant to Mollie, so they did.
No one said they had to do it sober. Drinkingbudies!flowerpot.