I had a circle of close friends in high school, 4 guys. As happens in most groups, one ends up often being the butt of the joke. But taking notice of this, we always asked him if he was alright with it or if he wanted us to stop. He always said it was fine, until one day it wasn't. Turns out he had never been fine with it but just said he was and one day he exploded on me specifically despite the fact I rarely teased him about anything, I was in a bad mood at the time and exploded back in his face.

About a year later I saw him again at a party and we reconciled, we don't dislike eachother, we recognise the mistakes that were made. But we have never become friends again after that.