Good luck. If you have the option, I'd take your own vehicle and have an escape plan should the cravings hit. Put your recovery first. There will be plenty of other family gatherings in your future and there's no shame in leaving if it keeps you from drinking. At the very least, stepping away and taking a long walk for 15-30 minutes could also be an option.
I'd bring your own non-alcoholic drink of choice as well. Keep it close at hand at all times. Also if you have a smartphone, pop in here when you can. Maybe use this thread as a base to check in every now and then and build some accountability.
You can do this! You don't have to take that first drink no matter what.