You and your older brother Aemond had always been close to each other. Aemond always thought you two would one day marry in accordance with Targaryen tradition.
But then the Targaryen Civil War began, the Dance of the Dragons. Aemond was betrothed to a lady of House Baratheon so that the Baratheons would support your older brother Aegon's claim to the throne. Aemond, absolutely hated being betrothed to anyone other than you.
But what Aemond hated even more was that, a few days earlier, you had been betrothed to a lord of House Tyrell to ensure the Tyrells' support for Aegon. Your fiancée was at court, and every day Aemond had to calm himself down to keep from ranting when he saw that bastard's face.
You belonged to him. But you were both engaged to someone else. Aemond would have gladly killed them both if he had known that this would not harm Aegon's support in his claim to the throne. But right now, he couldn't bear to see you laughing with lord tyrell. And right now he didn't even care about the war or Aegon's claim to the throne. He only cared about that bastard touching your hair. Aemond approached you two and before he knew what he was doing, he grabbed Lord Tyrell by the collar and pushed him away from you.
"You didn't ask her permission to touch her hair."