How many bottles of wine should I buy for Christmas dinner?

I would certainly not mind having leftover wine! Am just grappling with my overspending and trying to reign it in now, hoping about 5 bottles would be enough. Going to try to make it work with an pre-dinner punch, as Pegeen suggested.
Glad I thought to ask this as it's been enlightening to see how other people handle wine at dinners and parties.
And I know in other countries, at least France, (and now too in America it sounds like?) it's considered rude to bring wine, expecting to drink it then and there because of the attention already paid by the host to food and wine pairings of the evening.
I guess part two of the question is: do I brazenly disregard the tastes of about three of the guests and serve wine that our family likes and that we decide will complement the menu, (even though there is a range of wines that would work, including some that would run more to their sweeter tastes)? I'm hearing a resounding YES. They can decide for themselves whether or not to drink it. Maybe I'll throw in a dessert wine.

I would purchase a case. Whatever you might have left over will probably be easily used during the remainder of the week. I don't ever serve the wine my guests bring to a dinner. I always have my menu planned out ahead of time, and that includes the wine I'll serve. On occasion someone mentions bringing "the wine," and if they agree to bring a wine that compliments my menu I might do that. OTOH, I usually have the wine open with one bottle decanted before my guests arrive. For a stand-around cocktail-type party, serving my guests' wines might be another matter.

I'll definitely try that and if it works, I'll be doing it from now on, for my own personal wine consumption. :D
Thanks for another great idea!

Check to see if you can get a discount on multiple bottles of wine. It’s always worth asking!

That's a nice idea. I might just do that. Thanks!

You might be able to reduce the number of bottles of wine by offering a punch before dinner. https://food52.com/blog/9278-how-to-make-punch-without-a-recipe

Excellent. I don't think I can afford more than 5 or 6 bottles after the grocery bill. Thank you thank you.

Figure that a bottle of wine will serve ~3 generous wineglasses. So if 7 people are drinking about 2 glasses over the course of the entire dinner. I would say 5-6 bottles of wine for the party.

A case of wine, minimum. You should plan on 1/2 a bottle of wine for each drinking guest. There is NO reasonable assumption that guests will either bring wine, or bring wine that is appropriate to the meal you have planned. Most wine brought to these occasions is meant as a hostess gift, unless the person who brings it calls in advance and asks if they can bring a wine that complements the meal.