Cas was probably the only thing keeping her from entirely going off the deep end in this whole damned situation. So when he seemed upset there wasn't a question in her mind to take his mind off the awful things in the tape. Jo for her part was on the whole not watching team. She already knew some of the things she would see, she already knew the world was going to hell and the harder it got to hold onto the knowing she had before of that time when it would finally all be okay the more she didn't want to watch. It would be too hard.
So she grabbed a jacket and darted out in the rain to head over to Castiel's cabin. If there was one thing Jo knew, it was how it felt to loose people. It seemed that's all her life had really been, one loss after another. And when she walked up to him and took one look at him she knew that behind the carefully placed stoic look there was undeniable pain. She'd never really been a hugger but right then she couldn't stop herself from closing the space between them and wrapping her arms around Cas. "I'm sorry," she said quietly, though in reality all the I'm sorry's didn't mean a thing, they didn't change anything.