Okay, so, I know I should be posting a new chapter of my other stories (new "Grief" chapter uploaded tomorrow, promise!), but this little idea took hold of me on Saturday and wouldn't leave me alone.

So I started writing, and it grew into this.

It's already all the way written, so I'll upload one a day until it's done.

Serious Caskett. Esplanie and Ryan/Jenny are mentioned too.

I'll also be posting "Songs of the Chapter". You can listen to them while you're reading if you want, but it's not a songfic or anything like that.

Song of the chapter: "Just Breathe" by Pearl Jam

Disclaimer: I don't own Castle, or anything affiliated with it.

OK, I'll shut up now. Enjoy. (:

May 14th, 2012:

Kate examined herself in the mirror, smoothing the stomach on her gown. Her hands shook and she felt sick to her stomach, but she had no idea why. This was supposed to be the happiest day of her life, right?

And yet, for some reason, her mind wouldn't stop wandering. She thought about her mom, of course. She also thought about her dad and her friends, how unhappy they had all looked earlier, and about how unreal this all felt.

And of course, for a long time, she thought about Castle.

She was trying to push him from her mind when there was a knock on the door.

"It's open." She called.

Castle poked his head in. "Even for me?"

Kate smiled softly. "Yeah. Of course."

"Great." He walked the rest of the way into the room and took her in. His breath caught in his throat, and he felt his heart start to beat faster in his chest. "You're beautiful." He told her, smiling in spite of how much he wished she wasn't doing this.

"Oh, thanks." She said quietly. "It's this dress. It's gorgeous."

"No." Castle corrected, walking forward until he was only a couple feet from her. "I said you're beautiful." He locked eyes with her. "It's got next to nothing to do with the dress, Kate." He explained almost in a whisper.

She smiled at him and took his hand, giving it a squeeze. "Thanks, Rick."

He caught something in her voice, and tilted his head. "Everything okay?"

"Yeah." Kate nodded and offered up an obviously insincere smile. "Everything's perfect."

"Except?"

Kate sighed. He always could see right through her. "It's just…I don't know…"

"Kate, if you're having doubts, now's the time to say them." Castle said seriously. "You can still back out."

"No, no, no, no." She shook her head quickly, turning away and walking over to the couch. "It's not…I mean they're not doubts per se…"

"Then what are they?" He asked her, concern showing in his deep blue eyes.

Kate looked at her hands. "I don't know…it's just that everyone is acting so weird, and I feel sick and…" she trailed off.

"That sounds a lot like doubt to me." He pointed out quietly.

"I'm sure its just nerves." Kate said unconvincingly, glancing up and offering a fake smile. "Besides, everyone's already here." She cast a nervous look at the door.

He began to walk towards her. "Everyone being here isn't a good reason to marry someone."

"That's not why I'm marrying him." Kate insisted, sounding defensive. "Josh is a good man, and he loves me."

"But do you love him?"

The question caught her off guard, and she stared up at Castle, green eyes wide and her mouth opening and closing a few times, the question hanging in the air. "…Yes." She said finally.

Whatever hope that had bubbled up in Castle's chest faded away. "Okay." He nodded, forcing a smile. "Then that's all you'll ever need to know. As long as you love each other, it'll work. You have nothing to be nervous about."

Kate stood and hugged him tightly. "Thanks, Rick." She said again.

"Not a problem." He told her, rubbing her back lightly. "Josh is a lucky man to have you."

She took a step back and walked back over to the mirror and began putting her earrings in. "Don't worry, Castle, you'll find someone."

Castle shook his head. "Once again, not what I meant. I didn't say someone like you, I said – and meant – you." He let that sink in for a moment. "If Josh ever stops appreciating that, let me know. Alright?" Then he left.

Castle sat in the very front row.

He sat next to everyone from the 12th, all of them (even Lanie who stood next to Kate as Maid of Honor) with large and obviously fake smiles that mirrored his own.

He heard everyone gasp when Kate – his Kate – began to walk down the isle, and knew no one, not even Josh, appreciated that beauty as much as he did.

He thought about what their life would have been like. She could have moved in with him, Alexis, and Martha. She was already family, the transition would have been easy, simple, seamless. They would have all played laser tag on the weekends, thrown Halloween parties, and summered in the Hamptons. He would have personally seen to it that she never wanted or needed and was always happy.

And he was sure that her life with Josh would be fine just fine, with a yellow house in the suburbs and two perfect children and a dog. He knew she probably wouldn't be unhappy, and that she would do things like cook every night, and do laundry on the weekends. She would go to T-Ball games for her kids, and take family trips to Disney World, and celebrate anniversaries at a decent restaurant that she couldn't take her kids to because they didn't like anything on the menu. In all respects, he was certain that her life would be perfect in an almost unreal and separated way.

But Katherine (as of now) Beckett was extraordinary, and she deserved an extraordinary life.

He saw Kate looking at him nervously from the altar, so he sucked it up and gave her a smile and a thumbs up, and sat in the very front row, and watched the woman he loved marry someone else.

It was the hardest thing he ever had to do.

As she walked down the isle, she felt dizzy, and had to fight to keep the smile on her face and her eyes on Josh, when all she wanted to do was run. Run, and run, and run, and not stop until she was somewhere safe and far away. But she kept moving. Step by step down that isle that looked all too short. She told herself that it was just nerves, and that she would feel better when this day was over, but deep down she knew that wasn't true.

All too soon she stood at the altar in front of Josh, and suddenly a grave sense of reality hit her. This was it. If really was a One-and-Done kind of girl, then this was the end of life, as she knew it.

The ceremony went on around her, as she was lost in thought. Josh was good for her. She supposed she loved him, at least in a sense. Being with Josh was…uncomplicated. Easy. Simple. Comfortable. With Josh she didn't have to feel very much at all, so there was almost no risk of getting hurt. Josh was so normal. There was nothing to figure out.

She looked out and saw Castle and felt her heart pang. Castle and her would never work. Sad, but true. Maybe if they didn't work together, maybe if she didn't already care so much about him, maybe if she wasn't so terrified of getting her heart broken…she loved Richard Castle with all her heart. She would always feel that way, and she was well aware of that. She just hoped that given plenty of time and a decent alternative she could bear it.

Castle seemed to snap out of his thoughts, and gave her a thumbs up and a smile. So she tore her eyes away from Castle and said, "I do."

It was the hardest thing she ever had to.

While I was writing this, my Microsoft Word kept wanting to de-capitalize Josh's name.

Review for Caskett shipping computers? (;