Prepare yourself with a plan. Sooner or later you'll probably be in a similar situation. Practice in your mind's eye being there. You can't avoid situations forever. Alreadu have a soft drink or picture yourself saying no thank you....If they ask why I'd ask for a soda or a water....picture that. Imagine having a great time with your friends, no fear or anxiety, being comfortable and feeling strong in the fact that you're sober and you don't need it. (Be sure of your underlying motives for going...that it isn't to drink)