Suetonius Tiberius 10

Surrounded by all this prosperity, in the prime of life and in excellent health, he suddenly formed the resolution of withdrawing to a greater distance from Rome . ¹ It is uncertain whether this was the result of disgust for his wife, whom he neither durst accuse nor divorce, and the connection with whom became every day more intolerable; or to prevent that indifference towards him, which his constant residence in the city might produce; or in the hope of supporting and improving by absence his authority in the state, if the public should have occasion for his service. Some are of opinion, that as Augustus's sons were now grown up to years of maturity, he voluntarily relinquished the possession he had long enjoyed of the second place in the government, as Agrippa had done before him; who, when M. Marcellus was advanced to public offices, retired to Mitylene , that he might not seem to stand in the way of his promotion, or in any respect lessen him by his presence. The same reason likewise Tiberius gave afterwards for his retirement; but his pretext at this time was, that he was satiated with honours, and desirous of being relieved from the fatigue of business; requesting therefore that he might have leave to withdraw. And neither the earnest entreaties of his mother, nor the complaint of his father-in-law made even in the senate, that he was deserted by him, could prevail upon him to alter his resolution. Upon their persisting in the design of detaining him, he refused to take any sustenance for four days together. At last, having obtained permission, leaving his wife and son at Rome , he proceeded to Ostia , ² without exchanging a word with those who attended him, and having embraced but very few persons at parting.