Just read back, and daphne, i didn't mean to make you feel bad for planning a night off. I think we're in different situations: I've got a few things each month that I go to (book club, meetings of a voluntary group I run, etc) that I would normally see as an opportunity to drink just a wee bit more than usual, and they come up every month. So every month I have 2-3 excuses to keep on drinking all the time. Just another way of burying my head! It's different for you, having a big event that's a looked-forward to, one-off.
The family norm thing I do find tricky. Are my parents alcoholics? Hard to say. I did post about this ages ago on here, and the responses were varied. I guess it depends how you define alcoholic. Certainly they, and I, drink more than the recommended guidelines. But they are never 'drunk', they can stop when they need to (if driving, or for medical reasons). So the fact that they drink every day, yet life continues as usual with no dramas, it's hard to see why they (or I should stop).
Another reason... I am aware that my children have seen me drinking pretty much every single day. A cold beer while cooking, then wine with dinner. So it's normalising it for them too. But they've never seen me drunk, as in falling asleep / over, drunk. We live in France where I'd say the attitude to alcohol is rather different, a lot less binge drinking and a lot more '1 glass with dinner and that's it'.