She saw him watching her. She could feel his silver eyes upon her back, protecting her. She knew he loved her. It was fairly obvious in the way he looked at her, the way he always jumped between her and any other danger.
She didn't love him, at least not in the way he loved her. He was her brother, and she would've given her life to save him. Yet it wasn't his arms she imagined around her at night, but rather his best friend, James. James was kind, nice, helped her with Transfiguration. He was there when she wanted him, and he wasn't when she didn't. It wasn't that Sirius wasn't, but rather the fact that she had always known, even back in her first years, that she was James', and James was hers.
She would always love Sirius; he was one of her best friends. But she would always be James', and no one else's. There was just no room for Sirius.
When she and James started dating, he disappeared for almost two days. She was exhausted from worrying, and she was happy when they found him. She knew why he was gone, and felt horrible about it.
And then she and James were married. No one could find him, and she was fraught with nerves. When Marlene finally found him, he ecstatic.
But she wasn't as happy as she should be, because there was an ocean of pain behind his stormy eyes, and the skin around them were puffy, like he had been crying for a long time.
She felt horrible, but what was she supposed to do? She loved James, and she didn't love Sirius the way he wanted her to. It would hurt him more, wouldn't it, to be with someone who didn't love you and loved your best friend?
Lily married James, and it was amazing. But Sirius's pain was on her mind, too, that night.
Harry was born. She was so happy. He looked like James, except for his eyes. He had her eyes.
And then Voldemort came. He broke through the Fidelious charm, and Lily knew they shouldn't have trusted Peter. But it was too late.
Her mind lingered on Harry and James, and there was a veil of sadness in the back of her mind, for Sirius, for what could've been, and what never would.