Doyle's been coasting a bit the last seven months or so. You may have noticed that he's drinking more, though he's been avoiding the brothel. The few times he has gone there, it's definitely been for one of the girls. Yes, he's avoiding Ryan.
But he's not letting it affect his duties. In fact, he's thrown himself into his work as a teacher even more than before. So the kids, at least, probably won't have noticed much wrong.