I'm still rather confused as to how you have a monolithic 'party' which is being acted against by one player.
There Wheaton Rule is a good rule of thumb, but I can't get behind your call for subsuming all conflict into the will of the collective. Firstly because I don't believe such a collective actually can exist, it's a bunch of people not a mindmeld, and secondly, conflict can make a game awesome, so long as it's not violating the Wheaton Rule.
I don't call for subsuming all conflict into the will of the collective for starters and I'm addressing the pathological case. If the situation has grown so dire that the player cannot conceive of continuing play and remaining true to the characterization of the PC, that's a good indication the character is a poor fit to the group.
I'm of the opinion that the responsibility of not stalling the game/breaking the party lies on the player that is introducing the conflict. Feel free to conflict away as much as you wish -- so long as you aren't raising blocks that prevent others from enjoying themselves. If a character is offended by behaviour typical to that group, it isn't a group problem; it is that player's problem to work through.
Roleplaying is a social activity. If a person isn't enjoying a group activity, by all means discuss with others what you don't like. However, it is the responsibility of outliers in any group to take remedial action if the group rejects the appeal. A PC can be constructed with traits, values, and principles, but the player needs to understand where the group behavioural expectations lie and colour inside those lines when portraying them. For some groups that means no sexual violence; for other groups that means murder-hobos wreaking havoc.
There is a difference between a trait and the action a PC takes because of it. A player can almost always play true to the trait without blocking the table. If A is doing something that is blocking B and C because of some internal reason ("I'm playing my alignment!/My character wouldn't do that!/I won't hurt animals even if they're imaginary!") then A has to be the prime motivator of any solution because there is only one solution that doesn't require A's acceptance and it is a simple one: get rid of the annoyance.