Charles feels betrayed, of course he does. Erik went off and married another woman. And had twins with her, which now Erik is begging Charles to help him find. Charles can't a complain too much, he has Moira. But that doesn't mean this doesn't hurt. (set after XMEN: Apocalypse but I have changed parts of the movie, like the fact that in the movie Erik had a wife and daughter who died, whereas in this fanfic that doesn't happen to Erik)