I think we alienate ourselves in our heads way more than what is actually going on in real life. "I need to drink to have fun." "Everyone will notice I am not drinking." Etc... Take a minute and think about how much time you actually think about or worry about what someone else is doing, for me I usually notice what others are doing but dont put much thought into it. I bet the same applies to most other people.
I like what Xune said above. You dont drink anymore. If someone calls you on it, just say you set a goal for yourself to not drink for a while. Anyone who doesnt respect your goals, doesnt deserve your respect. Have fun at your events!