Hestia felt her heart drop a little. His best friend. Of course she was his best friend. She always would be. But... well. For a moment she considered asking him if she was more than his friend, but Hestia couldn't bring herself to do it. Bill Weasley always went after what he wanted in life and if he wanted her to be something more, he'd tell her.
She tucked her head under his chin and closed her eyes, content to be close to him. One day, she knew, Bill was going to find someone pretty and exotic and mysterious like Fleur had been. He was going to find someone who had seen the world like he had, or someone who craved adventure. And their intimate time together would become a memory, nothing more than her being there for him when he was struggling.
"Oh," she said quietly. Hestia couldn't quite keep the twinge of disappointment out of her voice. "Of course," she continued, "I understand. I know you're busy."