Paul's letter to the Galatians is really an admonishment more than anything. He founded the church in Galatia, went on to plant other churches around the Mediterranean and then hears of their fighting among themselves and how many in the community had even turned against him. In today's passage, he's essentially asking - What happened?
Isn't that true in our lives sometimes? Things seem to be moving along quite nicely and then something happens, someone says something that is surprising or even shocking and then suddenly everything is different. We look at that person differently, maybe we are even disappointed to the point of looking at the world differently. We wonder where that thought came from? Why was that statement said? We feel betrayed by it. How is it that someone we care about could be so callous ... so mean? We have been turned on.
This is how Paul felt and Paul responded with the letter to the Galatians. In it he recalls the strong relationship he has with that church, he reminds them of when we first arrived in Galatia and how he was so overwhelmingly welcomed and fundamentally that regardless of our differences we are one Body in Christ. We all must work together for the Gospel - certainly not fight among ourselves.
Our response when we have these experiences could be the same - to remember why we are in relationship with those with whom we are in a disagreement. Remember how we started, what drew us to each other in the first place. Remember the fundamentals. If we remember why we care for each other, the reason we are arguing will really seem minuscule in comparison. We are all different. We don't always behave in ways in which we are proud, but in the end we are one. We need to remember what is important, forgive each other, and move on.