For a moment, his eyes were wide with surprised pleasure, and then reality kicked in. The man had three children, a career...Snape. Remus had the kind of life that Harry wouldn't, couldn't intrude on. For a few scant months, Harry had two fathers, and it hadn't made a bit of difference. He still ended up alone, and he wasn't about to let Remus try to step into a doomed role.
"There's nothing to forgive," he said, voice husky. There was no need to alienate Remus now by trying to explain. In a few weeks, everyone else would be back in their normal lives and Harry could get on with the business of existing.