Sirius didn't want to apologize for the way things had gone last time, though it was on the tip of his tongue, or even to admit that maybe he could have explained better, but he'd been so angry. It didn't matter how many years had passed, what happened to Lily and James would always be a bright shining spot of pain in his life. The understanding that he had been so thoroughly betrayed by someone he'd trusted with not only his own life, but the lives of the people he loved most was devastating.
"The whole point was that people thought it was me." He said instead of admitting anything. Just like the rest of the world had assumed it was him, of course Severus did too. "I thought maybe - maybe they'd come for me." He said, he'd been prepared for that, to have someone come to kill him instead as long as it meant that his friends were safe.
Nothing had worked out the way it was supposed to though. "I'd have never -" He started and stopped, "I'd have died before I let anything happen to them if I could have."