One day, the girl in the mirror is a stranger.
Not much has changed, for a casual looker there is nothing different to see. She, of course, sees it straight away. After all she looks into those eyes every day, and this is not what she expected to see. The day before had changed everything, but she hadn't thought it had the power to change her also.
She carefully goes over each detail. The high cheekbones, the somewhat upturned nose, a few unruly curls in the otherwise tame hair. All of these things are familiar. So is the dimple on the right cheek. Except it shouldn't be there. She shouldn't be smiling, not after yesterday. The lips curve the familiar way, but the smile is all wrong because of the eyes. The familiar twinkle is gone. It has always been there, can be seen even in the baby pictures, but now it's missing.
She watches as the stranger in the mirror builds shields and locks her inside them. And she lets it happen, because then she'll be safe from hurt, from the world. Then she can be strong and support those she knows need her help, even if they would never acknowledge it. She becomes the stranger in the mirror.
Years pass. She learns to stand tall, to break, to pick herself up. To shatter and build herself up again. And one day, the girl in the mirror, now more a woman really, is a stranger once again. And she knows this time it will be an easy role to accept.
This time, the stranger has a twinkle in her eyes, and the dimple doesn't seem so out of place.