Honestly I could never picture Barrons saying those words out loud unless he really thought she was dying. I also figure by not saying them he's protecting her. Imagine what Ryodan and the men would do/want to do if Barrons proclaimed his love out loud. When he told her ily in his own way at the end he asked her if she understood. In a way he was telling her without saying the three words. He wanted to make sure she knew what exactly he was telling her.