You might want to read the backstory (again) of each character first... the links are in the story. I suggest you start with Margaret, and then Neville.
The Day of Days
They stood in front of Rev. Dalripple, friends and family in the pews behind them, flowers lined the altar, and the last notes of the organ settled into the end of the day's light as it came though the windows above them all.
Neville had watched his Margaret (oh! How he loved saying 'his' Margaret!) as she walked up the aisle towards him, her right hand resting in the crook of her father's arm, her left holding the bouquet of the lilies she chose to carry. Their colour was a shade off from her wedding dress from Cassini. It's silk folds whispered 'Paris Couture' with ever step she took, skimming her body then going into a train from the full skirt.
She smiled in that Margaret fashion, looking towards him steadily through the veil over her face. He shook slightly, still awed he was to be part of her world, that their lives would be intertwined throughout all the things that occur in a marriage...that eventually, they would have children he would love partly because they were half Margaret.
Facing each other, veil back over her head, the ring firmly in place on her finger...the last of the Reverends words had been spoken, waiting for them to follow his directions. "You may kiss your bride!", he'd announced quite loudly, and all of them waited. Margaret looked up into Neville's eyes, her smile not quite reaching her own. He knew then why she'd been so silent in the last weeks, why she avoided the last part of her time in Paris in her conversations. He knew, and it made no difference to him.
"It's fine, my dear. All is well.", he whispered as he leaned forward to kiss her.
With that, Margaret discovered you can fall in love more than once in your life, that the one will never wipe out the other. She smiled into Neville's kiss, leaning into it fully, her hands on his broad shoulders; shoulders she knew would hold more than his share of trouble in their world.
Turning to the full church, they paused for a moment--two people who knew they were meant for each other, willing to accept the good and forgive the bad... two people who would go through their lives together, knowing at the end of it all, they could close their eyes that last time, content in the belief they had been beloved by the other.
Stepping down from the altar, they walked into that future with matched steps.