be depressed
悒 centers on a heavy, inward emotional state: feeling depressed, gloomy, or weighed down by worry.
悒 combines the heart radical 忄 with 邑, which likely contributes the sound and may suggest a confined or inward-turning feeling, fitting the depressed meaning.
The heart 忄 is trapped inside a walled town 邑, unable to get out. That heavy, confined feeling is depression.
For ユウ, imagine a depressed person sighing 'you' in a low, drawn-out voice: 'yooou...' The sound 'you' cues ユウ while the heart stays trapped in the town.
sad; melancholy