One of the members of our group likes to choose characters with personal agendas or secret motives that prevent him from cooperating with the rest of the team. He will sit out of missions entirely if he feels like they go against his character's motives.
This would be alright if he did not affect the other players, but that isn't always the case. Once during an important battle, he targeted a player character instead of fighting with us. (He tied this player up, making it impossible for them to do anything except try to escape on their turn. They were in a pretty sour mood because of this.) The GM did their best to make sure we weren't punished because of him, but everyone got pretty frustrated and we had to call the game. The players and the GM have talked with him about this, but he has made it clear that this is how he enjoys playing campaigns.
Is this something anyone has dealt with before? How should we deal with an overly stubborn player?
