Accidentally Insulting A Friend is the 214th Subnormality comic.
Plot Summary Edit
PHG is giving Ethel a lift because Ethel's car is broken down, and Ethel sees a quiz on PHG's phone. PHG says she scored six out of ten, and Ethel comments that she should find it easy, accidentally implying that she thinks PHG is stupider than her. PHG brings the car to a sudden halt at a red light.
The comic splits in two, showing Ethel and PHG's thought processes separately. Ethel is horrified by her mistake - although a part of her wants to feel superior, and another part wants to pretend it never happened and let it blow over, she ultimately decides she has to apologise. PHG is hurt by the insult and reflexively wants to insult Ethel in return, but realises that a small jibe would be an out-of-character way for the often-scathing Ethel to show displeasure, and blames herself for being too sensitive about her insecurities.
The light turns green, and the comic returns to reality. Ethel quickly apologises, clearly upset, while PHG laughs it off. They both comment that "If you could see inside my head..."