Perhaps there's something going on in his life that's causing him to be distracted or not in the right mindset to watch your stories. Maybe he's dealing with personal issues or stress.
Maybe he's just lurking and not in the mood to text right now. Sometimes people enjoy seeing what others are up to without feeling the need to communicate.
Well, there could be various reasons. Maybe he's got some personal issues on his mind and doesn't have the mental space for your stories. Or it might be that he's trying to distance himself for a while for no particular reason. It's hard to say for sure without knowing more about the situation.