Backwards
Everything was so wrong.
Sometimes, he wanted to think it was his fault, Harry's—anyone's, just to have someone to blame. Sometimes things hurt less when there was a reason, when it could be laid out and looked at logically, dissected and all the different aspects labeled and set into place.
But there was nothing logical about Sirius' death.
That made it hurt worse than anything.
Sometimes, it didn't matter, and all he wanted was to forget it even happened.
But sometimes, rare in the midst of the guilt and the anger and the hatred, sometimes there were those scarce moments of hope, when Lupin thought that he could bring him back.
It was all so wrong, all so terribly wrong, like a messy desk, cluttered with disorganized work that needed to be put back in order. It could be that simple, if he hoped hard enough.
But he couldn't do anything over again, and could never, ever go back to that moment.
No one can go backwards in time.