If there's one thing I've realized during the past 20 years of sobriety, it's that most people don't act predictably. One of the reasons alcoholics are drawn to it is because we are sensitive to others to the point of detriment.
It sounds like the experience you had was striking! I'm glad you choose to get it off your chest. I usually just avoid parties and taverns. I can't relate at all anymore.
But you're a good example to others. You may not have a lot of confidence yet. But you will if you continue on.