Oh he heard it, he did. He wasn't stupid. He just wasn't sure how to trust it. How to trust that she would remain loyal with Stefan in her life, with others turning her against him. He knew he didn't help matters, he was cruel, he was heartless and he laughed at her pain each and every time he took someone she loved from her. But he was trying with her, even the last time he'd put her down with a dagger, he hadn't wanted to, he hadn't been able even to look at her. But still, to be pitied.
"Well then I shall have to endevour not to lose control." he said simply. "Do you know what I've given up, and you might believe it simply for Caroline but its not. Katherine's life, letting you find happiness with Stefan, letting you leave me. I have shown so much mercy, so much restraint and yet all you see is the things I have not done. I don't control everything around me. Not here, not anymore. And you're right. It's difficult for me. I want to know that I can continue to trust you. That in a year, in ten, you won't have some manner of plot against me. That you, Kol, Elijah, that I can rely on you, that I'm not loosing you to..."
He paused, not wanting to say it, not wanting to lose them to anyone else.
"I believe you're loyal to me now. I do not know how long it will last."