Answer:
Dysthymia.
Step-by-step explanation:
Dysthymia may be defined as the medical condition of in which the person suffers from the long time depression. This condition is also known as Persistent depressive disorder.
Sean is hardly happy and does not eat much food and is highly depressed. He has been suffering from the depression for the long period of time. The diagnosis for Sean is dysthymia. He must be treated by giving anti-depressant drugs.
Thus, the answer is dysthymia.