As a lifetime non-drinker (I'm allergic and very old) I can assure you that if anything, it will work in your favour. I was lucky enough to have a car as a student andI therefore got asked to a LOT of parties because I was a safe and reliable form of transport who would make sure people got home ok! Even if you don't have a car, there's a lot to be said for having one member of the group who can still make rational decisions in times of crisis. I have never needed alcohol to make an idiot of myself in public, either, so I don't think I stood out.... Don't be pressurised. If it's not for you, it's not for you and any 'friend' who dumps you on those grounds is not a person worthy of your time.