I pretty much assumed his teacher wouldn't survive the episode, as there hasn't been any mention/sight of him since Morgan came back last season. Touching character, but I was more upset when Tabitha died
The more I think about the whole Glenn thing, the more I'm convinced that he's dead/going to die from a bite. I keep going back to that scene where he was piled on by three or four walkers because of Nicolas at the end of season 5, yet managed to escape without any bites or scratches. I think it's his characters downfall, his willingness to give someone who tried to kill him a second chance. That doesn't work in this world, and ultimately it's Nicolas that gets him killed. To me, it justifies Rick's craziness in killing anyone & everyone that poses a risk. Some people just can't be trusted, and Glenn could never see it that way.