Dear Audrey, so sorry for what sounds like a dreadful set-up for a very abusive bad couple of days. At least, you can know that you are in the hearts and prayers of many here on Sober Recovery so you don't feel so alone.
It sounds like there are many issues here in your relationships with your boyfriend that warrant some real thinking about, but the immediate crisis is what to do today and tomorrow.
If it were me, I'd just not go at all. Maybe to a church service, if that is part of this. If I did go, I'd do my best to have my own transportation. If that's not possible, I'd alert a taxi service to make sure you can call them to get home if you want to, and make sure you have enough cash to do it. Last resort, I'd be ready to take your boyfriend up on his offer of a ride home. If you can drive in this country, I'd take an extra car key so you can get yourself home, and someone else can drive your boyfriend home.
If I had to go, I'd pretend that I was visiting aliens from another planet who were very "good-behavior-challenged" and never for a moment think that you are going to have any normal pleasant polite interchanges with them. Perhaps imagine them as if they were wearing alien costumes and could only understand some incomprehensible language that you do not speak. That should help you detach and keep yourself amused and distanced. I might even go so far as to privately begin to compile a list of "bad-behavior rules" that their country promotes. Maybe, 1. no good turn goes without a corresponding bad response. 2. You get points for bad things said to people. 3. You get extra points if you say a bad thing loudly enough or in bad enough language that the other person responds....
Then count up the points....
Anything at all to detach from this and not take it personally.
If your ABF manages to get through this without drinking, that will be a major victory. I would hope for that and not expect much else - its too much a powder-keg of malicious entwined bad behavior by his entire family to hope for much else. The time to sort it out with him is later when he can have some time to get some perspective on what went on. You can invite him to leave with you, but until he can link his drinking to all these triggers, it will be hard for him in the moment.
The pinching your cheeks when you tell him to stop and other aggressive physical behavior is a real warning sign. Just keep yourself safe through this little hurricane of a holiday!
We'll be thinking of you, and sending GOOD FRIENDLY HELPFUL thoughts your way!
ShootingStar1