Open Wounds (Inside and Out) Beginning

Just the very beginning of a story. 500 words exactly.

She studies her face in the mirror; frigid turquoise eyes stare back, imitating the blank eyes of the dead. A sheet of white fabric floats idly around her black hairline, framing her pale, angular face. Absentmindedly, she brushes the cloth away before pressing her toughened hand against the glass, watching her mirror image do the same.
At least I have you.
Indecision lies in the curling of her youthful fingers, the worry of her lowered brow. Without a word she pulls the spider’s web of fabric over her face- an obscuring, shielding veil- and examines herself in the mirror.
Do I look the part of the jubilant bride?
She eases her lips into a masked, shy smile. She feels naked, though she’s wrapped in swaths of fabric. In the mirror, she resembles a doll dressed up in layers upon layers of heavenly snow. Just a mannequin, perhaps- a mold, practice for reality.
Maybe he won’t notice.
Pushing herself into motion, she mechanically makes her way out of her room, focusing on the rhythmic step of her feet. To her, the empty echo of her bare feet resounds far louder than the ringing church bells, indistinguishable from the echoing call of a funeral.  
One step at a time. Steady as she goes.
Perching at the end of the grand staircase lies a double door, surrounded by stained glass that obscures the scene awaiting her beyond. She eases herself down from the last stair-step, peeking out through the kaleidoscope of colors. An aisle stretches past rows and rows of unknown faces to a stage adorned with a nimiety of flowers.
There stands the man she doesn't love.
Is this worth it?
His back is turned, his face unseen; the man she wrongly accepted when he asked her to marry.
I would gratefully give my life to be a mosaic; incorruptible art, pieces of a beautiful memory. Creation that can never be given away.
With a deep breath and a strong force of will, she eases one of the doors ajar and marches out into the open.
All faces turn her way, curiosity lining their eyes. The man remains still, examining the depicture behind the priest before finally turning to meet his bride. She has no father’s hand to hold and simply clenches her fists instead.
Too late to turn back now.
She crosses the vast expanse and smiles up at him warily, taking his hand and squeezing it between her sweaty fingers. His cool gray eyes glance into hers- as stony as the rock they resemble- before turning back to the priest and his babble.
I’m terrified for all the wrong reasons.
She watches in a haze as the speech abruptly ends and is punctuated by dead silence from the onlookers.
The priest watches her eyes widen as he hands her the knife. A slim, rusted thing that’s been used many times. Anticipation fills the groom's eyes as he watches the blade indent her skin...