“I hated them for holding me prisoner!” Theon shouts about the Starks as a last resort, “I wanted to hurt them.”
But the most painful part about that is that it isn’t true. It’s a lie, a huge lie, because Theon doesn’t hate them. Exactly the opposite is true. He loves them, and he hates himself for it. He wants what they have. He wants Winterfell, he wants their home, and their family, and their land and legacy. He wants to be a part of that castle, he wants to force his blood into the bones of the building.
He’s both jealous of Robb, and he wants to be his equal, so he steals Robb’s home and tries to be its prince. He occupies the chair that Robb sat in after his own father and sister rejected him. He chose the family he was forced into instead of the one that gave him away. He wants to prove he can be a Greyjoy, that he can take from others, make them pay the iron price, and that he can be a Stark, and rule.
He wanted to be Theon Greyjoy, Prince of Winterfell, and soon he won’t even know his name.