In my opinion, I think it depends on the size of the fight and also what kind of fight it is. If it is just a little verbal disagreement that turns into an issue but not that big, you probably will remain friends. If it is a large sized physical fight and you end up hurting someone, there is a very high chance that you will never be friends again. Atticus was tolerating the insults that he was receiving. He did not find it enough to end any relationship with anyone. I think that just ignoring the insults is a very mature act of him. It is better to ignore it than to make yourself feel bad by letting yourself get affected by it. I can also see that Atticus is trying to spread this behavior to scout because she is young and does not understand that not letting it get to you works, she just thinks violence solves everything, but it does not. I would attempt to be like Atticus and not let anything negative impact me, but if I have to I will do something more significant about it, but never turn violent.
Comparison of words to describe blacks in the 1900s
Nigger Lover insult