Yeah, I could go on for AGES about the art of apologizing... I don't know why we've come to think of these back-handed, passive agressive comments as actual apologies, but it needs to stop. I can't count the amount of times I've lost it on people because they have the balls to look me in the eye and say "what? I already apologized!" after spewing something similar to this comic's subject matter.
In this specific instance, let me be clear - If you follow the words "I'm Sorry" with "If you _____" chances are you haven't apologized. You are, most likely, apologizing FOR that person's actions/statement. That's even more insulting then just sticking to your guns and not apologizing in the first place. It DOES NOT COUNT.