But before that, when he wandered off. I should have tried to find him.

I'm sorry, I know you want to help, but I think you're wrong. Maybe there are times and places for 'whoops, I tried my best, screwed the woofbeast in millions of ways, but I sure did give it my all' but the end of the world isn't one of them. After you asked others to follow you and trust in your decisions isn't one of them. When you failed someone who believed in you and really needed you isn't one of them.