Update . . .

I appreciate all the ears I bent retelling the Tale. It was traumatic, but we are recovering. I don't think he will leave again, but of course, I am wary of making an absolute statement on that.
The weekend was spent enforcing yard restrictions and not having much patience left to tolerate the least foul mood out of him. There was more yelling and loss of resolve and not good sleep.

He is going to see the councilor at school as I am concerned there are a myriad of frustrations he puts up with all day, only to come home and not know how to talk about it, or let it out constructively. Or maybe he doesn't want to talk to us. This has led to thoughts of a punching bag or similar physical therapy as well as making sure he's got his own space in our house to chill out and be alone when needed. He's really always very well behaved at school which means it's nearly impossible for his teachers (his whole schooling life) to picture him the least bit temperamental.

The Smokin' One and I believe we are good parents. Our kids are a reflection of their great inborn personalities, but also a testament to our raising them. And there's nothing on Earth better than a happy Youngest Cho-Boy. I want that guy around. I can appreciate the sentiment that he trusts in us enough to show us this ugly angry side, but we'd also like some reassurance that we're not completely screwing him up in some way.
We realize we could be more consistent and somehow "helpful" and that's where we might seek some guidance. At the risk of Over Analyzing the whole situation, we will probably call on a Professional. An outside perspective.

Not to eradicate bad moods or displays of temper or anger. Just to make sure he's balanced. Or at least not confused or overwhelmed. I am hoping I am over-thinking all of this. Lots of kids have gotten the bee in their bonnet to take off from home. I just want to make sure. It was too scary to not treat it as a possible wake up call, and I trust SomeOne will tell me to chill out if I need to. Even if they charge by the hour.