That guilty look does not inspire much reassurance, and Rey slides the bottle towards her and farther away for Carlisle. He isn't drinking himself into a depressive stupor over this.

"And perhaps he'd have not been able to pick up on your teachings, and taken that out on you instead of Sato. If he had the ability to mend his wounds, he could pick all the fights he wanted at the time with little regard for his own life, because that's what we do with that sort of shit," Rey says through her teeth. "Do you really think someone who threatened you to teach him that shit is going to use it for a better purpose than what he just did anyway?"

Regardless of what Shadow would have done, it's neither here nor there. But there's no point in being sad about it, and Rey isn't wasting any of her energy feeling sorry for the idiot.