There is so much stigma attached to university and drinking. Having just finished my first year at university I have realised that if you're not a big drinker then that's fine. People don't tend to have issues with you not drinking as long as you don't frown upon them doing it.
Who's to say you can't go out clubbing with your friends, yet not drink? You still get the social side of it and the lovely stories the next morning but you don't have to drink.?
You'll find that many people also tend to go out just once a week and are not up for drinking every night of the week.
Although I go out drinking around 4 times a week, two of my housemates don't drink or come out and we still have a really good friendship. You'll find that you will have many friends who don't tend to drink and if you really don't want to go out then you can hang with them.
Living right near Norwich and the UEA I can tell you that there are many other things to do, other than go out drinking. The more stigma you attach to drinking and yourself, the more others will pick up on it. It's a lifestyle choice you've made, if people can't accept it, then they are probably not the sort of people you want to be friends with.