This was a new beginning, a moment pledging devotion for even the times when it will be hard. Shirayuki is preparing for the biggest promise of her life, a vow that she will have to keep the rest of her life, and yet a vow she looks forward to, a vow that she is happy to not be making alone.
And with her, she has a small bouquet of Wisteria flowers, a promise and a sign really, of exactly what family she is entering, just how her life will be different. It's customary that any bride marrying one of the Wisterias, brings with her a bouquet of Wisteria. Haruto's words echo within her mind, just a reminder of what it was like, and as Shirayuki can remember, Haki once carried a bouquet of Wisteria as she went and met Izana at the altar.
It's a sign of a new beginning, but also a sign of the royal family that one is about to enter into, a reminder to be faithful, to have fidelity, to enter into this family without backing out or failing it in a sense.
She had her chances to say no before today, but she hadn't, so with her yes today, she must remain faithful even to the very responsibilities that can easily overwhelm. She's embarking on a new journey, one that is a little scary, just for all its unknowns and also for the difficulty of rising up in an area of life she is still new to.
Shirayuki knows how to be an herbalist, but she has been learning how to be a princess for some time now. After this, she will be one, and she will have to do that well, being committed to whatever that will look like and be.
Though really her deepest longing for today is to be with Zen, for that to be permanent, and to know that her gift of herself will be met with his gift of himself, that there is honest devotion there and a future together. Shirayuki is already looking forward to that very future, even as she begins her slow walk down the aisle to meet her soon to be husband at the altar.