James had always hated seeing the people he loved upset, and the very worst thing about everything Lily and Sirius were going through was that he couldn't seem to fix anything without hurting them, too. The amount of heartache he felt at Sirius's breakdown made his eyes sting as well, and he closed them, tightening his hold on his friend.
He understood it better now, that was the painful part. Or at least, he understood that Sirius saw what had happened to him as a betrayal to James; if he'd thought that when he was sixteen, there was a good chance he thought that now, too. That was, James assumed, what Sirius was apologizing for. Or part of it, at least.
It hadn't felt like a betrayal on James's end; the only people he held responsible were the Lestranges. He knew, without question, that Lily and Sirius never would have turned against him of their own free will. Their will had been taken away from them, that was the point. It hurt, but he wasn't going to hold that against them.
"You're my brother," he said, voice rough. "You'll always be my brother." He had intended to say more, perhaps to offer forgiveness, but the lump in his throat closed over and he couldn't get it out.