Unity is what Jesus asked the Father to give His people. Remember the night before he died? He said, "Make them one the way we're one"—one in shared values, one in shared outlook and perspective.
People who struggle alone are like a bowl full of BB's. They share their nearness to one another, but they are each separate—not in unity. What Jesus prayed is that the Father would somehow melt those BBs together and make them one family, one purpose, one team, one unit, one life. Can't you hear the Savior saying to the Father, "make them one; give them unity?" In other words, make them more like a tub of butter, instead of a bowl full of individual BBs.
Why? Because when the turmoil inevitably comes, and you turn over a bowl full of BBs, they scatter everywhere. Do the same thing to a tub of butter and it stays intact. So, in a very real sense, the tub of butter should be like the church, not the bowl of BBs.
Unity is not a natural thing. It's not what happens in the fleshly life. The fleshly life produces chaos, not unity.