Another one of your many great poems, William.
I really do love your poems, and this one is no exception.
Note: I didn't read the previous posts yet, because I wanted to give my raw opinion/first impressions after reading the poem. This is just my personal thoughts and interpretation:
This poem resonates with me, because I have been going through some changes in life starting in college and discovering more about myself and being comfortable with myself.
This is a poem about self-discovery and/or acceptance of one's true inner self.
The "she" in the poem sounds like she is also discovering her self as well, and is now expressing her true colors to the world at large.
She is scared, but she is committed to finding happiness within herself and starting a new path in life.
She knows that her outer self that is reflected in the mirror and in the photographs hides her internal struggle with finding out what role to play in the universe, and whether to express her true inner self to the world.
The person in the reflection in the mirror (and the person in the photo) does not reflect the person she feels she is on the inside.
A person can take on many "roles" and change through those roles due to time and/or the situations and context. There can be different aspects to a person.
For example, a woman can be a party girl at a club, but can transform back into a student teacher role the morning after. A woman can be a daughter who cries in her own mother's arms in one situation, and then becoming a comforting wife to her husband in another situation. A woman can be tough at her job as a policewoman at during the day, and then, later, maybe at night, she goes home and takes on the role of a gentle, nurturing mother to her toddler son. A person who seems aloof to other people may have a soft side in taking care of a stray kitten, and may even become more expressive when interacting with said kitten.
Going to back to "she": The idea to combine all these parts of her and to become a new person spread like wildfire in her mind, urging her to start her journey of self-discovery. She comes to term with who she is, and is not afraid to express all the facets of her overall being to the world.
Anyway, that's my thoughts.
Again, lovely poem!