Hmm, did you ask your friend if he actually lost his internet connection, which caused the game to go belly up, or do you think it was something that caused all of your to disconnect?

Either way, if you're organizing games with friends, try out the new ICO test server. Not many people use it so the lag might be better, and if it has more error reporting so if something goes wrong with your game again, the Devs can figure out what went wrong and fix it (you should probably post here to make sure they catch it).