Answer:
The implication is that she will forever be perceived as inadequate, and she will not be noticed. During the one summer, her one "day in the sun," (a metaphor for someone getting their time in the spotlight,) she is shunned and literally locked away in a closet, unable to experience the sun.
It’s saying that when you express that you want to go home your actually expressing that you want to go home to see the people you love which would be you family/friends because that is where you belong and want to be.