Her mental state which was not fine was always pushed aside and was never noticed or thought about because of the many problems that covered her.
"Outwardly cute she wields a shield with full strength"
On the outside, she always looks happy and fine and no one realizes how she is on the inside.
"Bitter sinks so deep into her body"
So much bitterness about the problem that resides in her.
"Silent if empty noisy if crowded"
He talks too much and looks happy when she is in a crowded environment or with friends around her but is very quiet about her problems when she is alone.
"Dark, gray, foggy, endlessly surround and string her"
Dark, gray, and foggy, symbolize the gloom that always surrounds her.
"The low cry in her heart is so loud but not heard"
Her heart was already very burdened and had cried a lot but the people around her never realized it because of her extraordinary pretense.