i think azula’s storyline is especially tragic because she gets written off simply as being crazy or cruel when really, she grew up in a highly political highly oppressive home environment where the threat of violence was constantly hanging over her head like a guillotine. the buildup to her ultimate psychotic break especially is almost poetic in how poignant it is, because it’s a very real reflection of very real events people who experience psychosis will experience in their daily lives.
it starts before then but the first moment you can really see the paranoia begin to take hold of azula is when mai and ty lee betray her at the boiling rock. azula says something to the effect of “you betrayed me, just like everyone else.” to azula, the act of betrayal is an inevitability, it is a promise that people are going to betray her at some point, and going by the patterns in her life she isn’t exactly unfounded in this belief. first her mother left, then zuko, then mai and ty lee, so really the only person she has had as a constant her entire life is her highly abusive and manipulative father.
and for all that he is abusive and manipulative he has never laid a hand on azula. the promise of pain and betrayal continues to stay just out of reach as long as she continues to push herself past the point of perfection— see her saying “almost perfect isn’t good enough” when she has a single hair out of place after performing lightning katas. she has always been the perfect child, and why wouldn’t she continue to follow and obey the man who has done nothing but praise her?
in a way, zuko’s mutilation at ozai’s hand was kind of cementing to azula that she will continue to be safe, and praised, and honored, as long as she doesn’t slip up; and that is where her constant need for perfection comes from. all azula has ever wanted is praise and attention and security, and the only person, in her mind, who has ever given that to her is her father. so the time when her mind finally begins to break after being under the weight of all this pressure for so long is when ozai tells her he’s leaving and she’s fire lord now.
because for all her life that she had so much power, it only goes so far as the title of princess. ozai is one of the only people in the world who holds more power than her. zuko, technically, as crown prince does as well since he would be the first to take the throne before azula herself but since he’s been banished he is no longer a player in this elaborate chess game where the rules are fluid that azula has been playing in her mind ever since childhood. so when the threat of ozai is no longer imminent, her brain goes, “oh, we’re safe now. we can stop holding on to these coping mechanisms and masking, because we’re safe now.” that’s where she begins to become paranoid that everyone is secretly plotting to kill her, because while she is now safe from ozai she also no longer has the routine and safety of ozai’s presence not only in the palace but in her life as a whole.
the final straw is when she hallucinates her mother in the mirror, who was the first person to “betray” her all those years ago. azula is, deep down, just a scared little girl who feels like she has no allies in the world. she’s conditioned herself into thinking that her father was on her side this entire time, because there was no other way for her to reasonably live with him without being in constant fear. that’s where she and zuko differ: while zuko had as much promise and power as she did, zuko also didn’t take to bending the way azula did, which is why ozai chose azula over zuko, because in ozai’s mind bending is the true epitome of power. zuko had always been “weaker” because he didn’t constantly seek praise and approval and was more willing to go his own way, and azula constantly sought praise and approval, which is what pushed her to strive for more than perfection at all times.
bending was an area that azula could find safety in, because it tied her to ozai and gave her an anchor to hold onto, and if zuko encroached onto her territory better than her in some way, that meant she was losing her safety net and her anchor. suddenly, azula could be in very real danger if zuko became better than her somehow, so the only way to keep that from happening was to constantly push him down.
there’s a lot of tragedy in azula’s story that goes unseen in favor of painting her as a crazy bitch. because while she is psychotic and does suffer from delusions, she isn’t a threat to anyone but herself if she had the proper support network. i cannot fault ursa or zuko or iroh for what they did, because ultimately ursa and zuko were at the whims of ozai. ursa was just trying to keep her children safe. zuko was just a child trying to survive and do what he felt was right. and iroh, now that his brother was fire lord, effectively held less power now than he did as an active general, and zuko was alone and injured with no allies in the world so of course he would try to help zuko.
azula just needed someone in her corner, but that someone was never there.