Sarcasm is an adjusted stress reaction.

Exactly! Blame Ozai, Mr Setting My Kid's Face On Fire Is Totes Good Discipline! Or Azulon, Mr I'll Punish My Son By Making Him Kill My Grandson. Or, of course, Sozin, Getting Over My Ex Through Genocide Is As Reasonable As My Imperialism Is Benevolent!

It's not that Azula's not responsible for her choices -- I love the approach taken with Zuko, that his decisions come from a bad place, but they're still his responsibilyu -- but vilifying Azula alone is not fair.