thats part of it. but she hated getting betrayed by her friends, watching over the whole fire nation alone and because her parents never taught her any better.

and its not only that she thought her mother like zuko better she thought her mom didnt like her.

i never knew i'll hate azula 100 percent!

i love azula

Azula was mostly favored by Ozai because of her talents, and he thought of her more of a weapon. Ursa favored Zuko, while she scolded Azula. Azula hd a cruel outlook because her father raised her that way- that you cannot be weak. Later in her life, when Zuko got burned, it just proved once again what would happen if she messed up, therefor becoming a perfectionist. And because Ursa showed more affection to Zuko and showed little to Azula, she looked to Ozai for some form of parental love- which she never did recieve. So Azula had almost no form of love and affection shown to her in her life, except for her friends which later betrayed her.

In Sozin's Comet, when Ozai pushed her away, she found out that she was little more than a puppet to him. And he no longer needed her. Zuko had Iroh and Ursa through most of his life, she had NOBODY. At least not for a long period of time. And in that family, betrayal wasn't exactly uncommon. She learned that controling people through fear was the only way they would stay. She wasn't doing it to be cruel, she was doing it because she secretly wanted someone to care for her.

It's more than 'just flipping out'. Do you have any idea what it would be like to have nobody say "I love you" or simply hold you when you're upset? She had to suck it up for fourteen years. All of these troubled thoughts build up inside until they twist your mind. She didn't 'flip out' because she didn't have any control anymore. Her own mind, as well as the people around her, betrayed her. She couldn't even trust herself.

Also, Zuko's life was different. He made it out because Ozai banished him, and Zuko even said: Banishment was the best thing you've done for my life.

By the way, Ozai never really 'loved' her. He praised her, meerly because she listend to what he said, and was sucessful and strong. If she wasn't any of those things, he would have disowned her.

So children, look up and understand what mental illness is before you bash/laugh about it. It's not even close to a joke.

^ Wow, I'm tense..

what NightFrog says is true. Ozai didn't love her, he just praised her so that she'd be a Perfectionist. Azula has showed many cruelties until her own mother Ursa once remarked "What is wrong with that child?"