He couldn't help feel both insulted and amused at her telling him about how he couldn't live his life. He had lived her current lifetime many times over and over. More time to forget things... More time to become stubborn.
He took note of her tone when she spoke about Clint, and studied the subtlety in her expression, hidden in her choice of words.
"Then give me your word" he replied, his tone straight forward. That tone, his expression, they all changed in a brief moment. He smiled and laughed softly. "What amuses me is that if I were I to tell, you would not believe me" he said. If Thor arrived, he would no doubt tell her, so why not tell her first? And did it really matter if she did not believe him anyway? In a way it did matter to him. He preferred people to believe him when he lied and sometimes when he told the truth. And sometimes he wanted confusion, conflict within a person when he told either. He always wanted a specific reaction. But with this truth? He didn't know what he wanted. He had never planned to sit down and spill truths to this woman. Especially truths so personal.