'Just-' Cass took a breath, stealing himself. 'Just read the letter,' he said biting his lip until he realised it was a good chance he'd bite through it if he kept doing it. His palms were sweaty and he was pretty sure he felt dizzy which was the only thing that kept him from pacing the room like a caged dog.
Caged was by the way a very good description of how he felt right now.
Maybe another trip abroad would be good. For a few months perhaps? Until this went away? Only even he knew that this wasn't going away, and unfortunately it affected Percy as much as himself and there was nothing he could do to stop that. Well Percy could, far too easily, though Cass was sure (desperately hoped) that Percy loved him too much for that.