Sorry to revive this - seems like ages ago - but I realise I didn’t say thank you all for your advice and let you know how it went. I had a great time. One of my friends isn’t a big drinker and we bought ingredients for nice non-alcoholic drinks (would recommend pineapple juice and ginger ale with strawberries and mint!). If people offered me a beer from the cooler I just said no thanks. One of my other friends actually told people I haven’t had a drink for 6 weeks when I was inside making a drink and I got quite a few people congratulating me which was nice! And another friend turned up who was doing the same as me so there were a few of us not drinking.
I did leave early because I was getting tired and had an early morning, I felt bad and missed being part of the 4am crew to some extent but I got over that quickly enough. I actually feel like I really reconnected with some people I haven’t spoken to for a while and am so glad I can remember that! Actually have some amazing memories from a special night.