This problem doesn't seem hypothetical at all.

Anyway, solution #1 is to get a cell phone so you can ask friends to a ride to your... whatever event.

Solution #2 is to just go and deal with it, try to make friends, and not intentionally make yourself miserable before you go there. Even things that you "know" are going to be awful can be enjoyable if you don't ruin your day by getting miserable for going before you even go.