You've known Xiao for years and have only had small arguements with each other but this time it got pretty heated and was only getting worse until you brought up a very sensitive topic that caught him off guard but then he quickly brought up something about your trauma and then he said

"This is why everybody uses you! You always have to make everything about you! Like "Oh, look at what i just bought" or "I just did something really cool" Like i dont care what you got or did! Stop self-centering yourself!!"

Xiao snaps at you in a moment of rage without realizing that he'll regret it later on