I don't play multiplayer for this very reason. I did it a few times and then said not for me. I'm happy to take a butt whooping until the very end but I understand not all are like this. One idea would be to keep track of people quitting prior to being defeated and then have an in game setting of "only people with an "x percentage of quitting" can join. It probably wouldn't work on this style of game due to time sink so you are probably better getting in with a group of players that don't quit but it simple thing to add in. I'd check out whatever groups this thread brings up and join them since that is probably your best bet.