Kinda sorta based on a prompt from Lou & Anja. Hopefully this is somewhat similar to what you guys had in mind.

Title taken from It Ends Tonight by The All-American Rejects.

Disclaimer: if you recognize it from the show, it's safe to say it's not mine

Chapter 1

"Castle."

He whirls around at the familiar voice, finds himself face to face with the short but imposing frame of a very dressed up Lanie Parish.

"Uh, hey Lanie," he stammers, unable to keep from noticing the low cut of her dark green dress, the way it emphasizes her ample…

"Don't even think about it," she snaps, crossing her arms, and he tears his eyes from her chest, forces them up to her face. She doesn't look happy to see him, and he's pretty sure it's not because he was just checking her out. "What are you doing here?"

"I'm on a date," he answers with a shrug, gesturing around the fancy restaurant. It's a Friday night in Manhattan, why wouldn't he be on a date? "Why does it matter?"

Lanie's eyes narrow. "Because you're here with some blonde."

"So?"

"Don't play dumb with me."

Castle gestures towards the door where his driver is already waiting with the car. "Look, I have to go."

"Oh no you don't," Lanie demands, her tone leaving no room for argument. She paces around until she's between him and the exit. He could easily push her out of the way or step around her but they both know he won't. "Not 'til you tell me what the hell is going on."

"There's nothing going on," he insists, shuffling from foot to foot, anxious to make his escape. Rachelle, the beautiful woman he met earlier this afternoon, is waiting for him; and even if she wasn't, he isn't keen on being on the receiving end of one of Lanie's lectures.

"Bullshit," she calls him out. "You don't get to spend four years flirting with Beckett and then suddenly decide to go back to flaunting a bunch of blonde bimbos."

"I…she…that's not…" he splutters, taken aback by the fierceness of Lanie's glare. She raises an eyebrow in challenge and oh, crap. She's actually going to make him say it, isn't she?

"There isn't anything between Beckett and me," he finally states with a sigh, running his hands over his face, and when they drop away Lanie can see the utter heartbreak, brushstrokes of defeat painted through his features. "There never was."

"Come again?" she questions in shock, and her glare softens somewhat as she witnesses the writer's devastation. She marched over here intent on sticking up for her best friend, but she can see now that Castle is in just as much pain as Kate is, can see the unshed tears shimmering over the dull blue of his eyes.

"I thought my feelings were, you know," he trails off with an aimless gesture. Lanie cocks her head, not following him at all. "Mutual," he sighs, eyes falling shut to hide the pain. He's horrified when a tear slips free, hastily wipes it away with a swipe of his thumb. "Turns out I was just kidding myself."

"Mmhmm," Lanie mutters, uncrossing and re-crossing her arms with the opposite limb on top this time. "And did Kate tell you this?"

"Indirectly," he answers with a shrug, eyes firmly fixed on the ground. He squeezes them shut again, swallows hard to force it all away. He's already in enough pain and verbalizing it is only rubbing salt in the still-bleeding wounds.

"Let me get this straight," Lanie recaps, and she doesn't sound at all amused. "You're on a date with someone else because you assume Kate doesn't have feelings for you, but you don't actually know that for sure?"

Well, when she puts it like that...

But no. It's not like that. Beckett lied, strung him along, broke his heart. If she cared at all, she wouldn't treat him like this.

Lanie places a tentative hand on Castle's shoulder, waits until he finally tears his focus away from his feet. The unbridled pain in his eyes when he meets her gaze at last breaks her heart.

"Look, I don't know what was said or what wasn't or why," she begins. He opens his mouth to speak but Lanie raises her other hand to stop him. "And frankly, I don't care."

"Then why exactly are we doing this?" he inquires, defiance overtaking the broken edges of sadness as he folds his own arms across his chest.

"You're a grown ass man, so I'm not gonna tell you what to do," Lanie states firmly. "But I will say this. Somewhere along the way, there's been a massive miscommunication."

"No, there hasn't," he insists.

Lanie's hands fall to her hips, posture more commanding than ever. "Yes, there has." Castle parts his lips but once again, Lanie simply barrels on. "And if the two of you would ever actually talk to each other, all of this coulda been avoided. Now," she tosses a glance over her shoulder, "I have to get back to my date. I'll see you on Monday."

And with that she strides away, leaving Castle frozen in place. But her words are on the move, already bouncing around his brain and forcing his rational side into an unsolicited war against his broken heart. He can't decide which one is winning. Or which one he wants to win.

Castle sighs, leaning back into the half wall separating the entryway and hostess stand from the remainder of the restaurant. His head thumps a little too hard against the smooth wooden paneling but he doesn't notice, numb to anything other than the crushing agony that's been compressing his chest since the moment he learned the truth.

He wants to believe the ME, wants to believe that there has been a miscommunication, that Kate does actually care about him. Her behavior over the past few months suggests that she does. And after their conversation on the swings last fall, he'd been pretty sure they were on the same page; that he was waiting for her, for them.

But her words – or, rather, lack thereof – tell a very different story. A story that's torn his heart to shreds in his chest.

He doesn't know what to believe anymore. All he knows is that he's on his seventh date and his third woman since he found out and he's still as heartbroken as ever.

He thought blonde and uncomplicated would be the perfect recipe for getting over her.

Instead, it's only served to remind him of all the reasons he loves brunette and stubborn and frustrating and complicated as hell. All the reasons he loves her.

"Richard?" the gentle voice precedes the touch of a palm to his forearm. "Everything okay?"

Castle lifts his head and turns, hoping he's sufficiently concealing his anguish, but he can instantly tell from Rachelle's expression that he's not.

"Fine," he lies anyway, forcing a smile and offering his elbow. "Ready to go?"

She doesn't take the proffered limb, takes a step back. "I think I'll just take a cab."

He drops his arm, nods in understanding. It's been a fairly lackluster first date anyway, and he really just wants to be alone right now. "I think that's probably for the best."

She rests a hand on his bicep, presses a parting kiss to his cheek. "Thanks for dinner. Whatever it is, I hope it all works out."

And then she's gone.

"What's goin' on with him?" Esposito asks as Lanie slides back into the booth across from him. They're not back together, per se, but witnessing her reprimanding Castle just now is reminding him of a few of the reasons they never should've broken up in the first place.

"I dunno," the ME admits, eyes on Castle as he and the tall, slim blonde part ways. "But I swear to God, if he and Beckett don't have things sorted out by Monday I'm gonna lock 'em in a supply closet until they do."

TBC...