I think it's just loneliness. It can do strange, strange things to a man, as you and I both well know. The boy finally found someone who accepted him without question, and he misplaced his adoration. He'll move on, I think they'll be friends again. Remus and I went through a million ups and downs. Far worse than their row.
I don't know why he trusts you so much, but he does and I'm glad. He needs someone he can let his guard down around, and you and Regulus win the prize for his complete adoration. He picked two good men to look up two, and I'm glad for that.
You told it in your own time, mate. No harm, no foul and whatnot. It's a big thing to divulge, and I don't blame you for holding it in. That was not a good time for me, I'm sorry I reacted like a dolt, but I know now and that's what matters.
Of course I know, I deal in the black market all the time. Don't worry. I'll get a crate of the stuff and store it up for you. You should have comforts, same as any visitor.