The longing painted across her features only served to highlight the contrast between Andy and the sisters who never spoke her name. His eyes meeting hers, Sirius simultaneously understood and balked at the idea, or at so openly showing that... ache. At least he had the decency to hide it, or at the very least, to be ashamed of it. But the two of them were different, he found the grace to recall. Andy had never needed to be hard or strong or aloof, never needed to be coolly calculating; she'd had Bella to protect her. She'd had a family, one that took care of the softer parts of itself. So maybe it was okay for her to show what he couldn't, even if it was only between them, that they hadn't just left their family- they'd lost their family.
Not that those words could ever be said out loud, not by him. Because Sirius did have family, he had James. But that somehow felt very different from the family she had. It was very much for the best that Ted wasn't around, something Sirius had only just considered. Ted Tonks was probably some perfectly nice guy, but for Sirius that was nothing more than an intellectual abstraction that had no chance of overwhelming the title 'the man who stole my cousin away.' Sirius was working on it, he really was, but it was difficult. It was difficult, with her sitting there, wanting things that couldn't be. She'd said she was happy, and he believed her, but when people said they were happy, they usually just meant they were more often happy than they were sad.
He couldn't help wondering if she'd been able to have both, her pureblood family and her muggle husband, if she'd have stayed. Neither answer would have made him happy, neither would have made him feel better, the implications were just too convoluted. And there was no point in asking, it wouldn't have changed anything, knowing either way. It would have just been more to think about, or more to try to not think about.
With something like a sigh, Sirius leaned his face against his other hand and let his eyes fall shut, concentrating on the warm places where their skin connected, applying just a little more pressure, one of his fingers settling a little more atop hers. Like he was testing out how much was okay, as if he was ingraining the exact amount of pressure into his memory.