Damon did not see the point of talking about his brother. To him, he was not relevant in this situation. Their marriage was between him and his wife, no one else.
"You." It was just about him and her.
As far as he was concerned, if Jules would like to return to his brother, she was free to do so. She could choose to divorce him, and he would not stop her.
But before that happened, he would fight for a chance to prove to her that she did not have to leave. They could have a life together with their son.
"I need you." That was as real as it could get. He knew he was not lying about that.
He had known that for years, probably since the first time she landed in his arms that fateful night. However, his stupid brain kept denying it.
He had locked every memory of her, then threw away the key, hoping he would forget about her. Unfortunately, she found a way to resurface into his life, leaving him no choice.