The old dog tiredly chased its tail. what is the adjective?

(i'm bad at sudden poems so don't yell at me i'm trying to represent sadness or something like that but its real hard)

at the age of 4, she thought everything was better.

she was innocent, she was joyful, despite the predictions about the bad weather.

at the age of 10, she started to figure things out.

in life, in its meaning, she started to doubt.

at the age of 14, she was filled with depression, anxiety and fear,

that nobody cared about her, and death was drawing near.

at the age of 17, her sleeves got longer, her will got shorter, until she couldn't take it anymore.

she left this earth with a rope, chair and to the heavens she would soar.

. a function is a relation in which each input has only one output. in the relation , y is a function of x, because for each input x (1, 2, 3, or 0), there is only one output y. x is not a function of y, because the input y = 3 has multiple outputs: x = 1 and x = 2.