Glad you persevered, that must have been rough. I personally would have offered to take them home after the game or call them a cab. There's a difference between hanging out with friends at a game, concert, whatever when drinking is also happening. Once the activities shift solely to drinking, that's when you need to cut your losses and head home IMHO.
You know drinking isn't an option, it's just your brain fooling with you in the face of incredible temptation to join in. If anything you should feel happy and proud that you are sober today. Imagine how your friends feel today..