This came to me and forced me to write it. I had been contemplating the idea for some time, since the season 3 finale actually. But had never sat down and sketched out the ideas. But two days ago, 'Halo' by Beyonce came on, and the worlds hit my muse something fierce.

In case you were living under a non-pop-aware rock -

Remember those walls I built

Well, baby they're tumbling down

And they didn't even put up a fight

They didn't even make up a sound

I found a way to let you in

But I never really had a doubt

The parallels were too much for my poor unused muse to handle. This came pouring out. A mashup, if you will, of my own thoughts and the song. Hopefully I've done it justice.

Also, a SPOILER ALERT for ... pretty much everything pre-Blue Butterfly (season 4x14).

She'd built a wall sometime in her life. Oh, she attributed it to her mother's murder. She liked to think that the cruel rip of Johanna Beckett from the world was the reason she shied away from a 'real' relationship, but that wasn't true.

Kate Beckett was already leaning toward adding more height to that wall for some time before her college years. Katherine Beckett during high school was wild, interesting and had boys following her about. She had already learned that she needed to be in control for dating to work to her advantage. That mantra had followed her into adulthood. She had already laid the foundations for a wall long before her mom died. But her death added more layers, built height, it essentially solidified the idea that she needed to brick herself inside.

She knew she was in trouble when Richard Castle kissed her cheek and stole files. She knew that her wall was in trouble when instead of taking Richard Castle home for a quick (albeit, most likely awesome) tumble she'd opted for a spicy one-liner and strut away. The walls shook when he showed up at the precinct the next day, bouncing in immaturity to follow her around. She did her best to keep him at arm's length. She thought at first that Richard Castle was interested in her, perhaps beyond the physical. There seemed to be something more to him, she wasn't entirely sure and as much as she liked the flirting and innuendoes she wasn't going to settle for anything less than what she wanted. After the break up with Will Sorensen, Kate knew that her next relationship was going to be an attempt for something more. She wanted a relationship with someone who would respect her, and her job, who would want her for all the things she was – the bad and the good. Kate wasn't expecting a fairy tale, just a promise and a commitment.

Lanie made same pointed remarks and she started thinking… perhaps Castle might be the person she was looking for, he had potential but she wanted to get to know him better. She needed more that the firings of attraction and lust. That wasn't enough for someone to overcome the wall.

But he had some weird thing happening with his first ex-wife. Meredith – the deep fried twinkie – came back to town and within minutes they were in bed together again. At least he didn't lie about it. She would have to give him points for that, Castle never lied to her. Kitten showed himself to be an intriguing mix of boyish selfishness and manly responsibility. Kate was strangely attracted to it. But there were some aspects of his personality she detested. They weren't aspects that were irretrievable, he could outgrow them, move past them, if he wanted. She'd already noticed a change in him, less jack ass still wise ass. But it was unsettling, how his actions (and yes, his innuendoes) and comments seemed to indicate he was interested in her.

Kate knew she'd given him a partial green light with that initial comment oh, you have no idea. So he should have been aware that there was a frisson of something between them. A possibility. He was following her around, so clearly he was interested. But, then an easy lay breezes through – an easy lay, but a complicated family situation – and he's still treating her exactly the same. Now, Kate isn't a prude, she isn't ignorant of that thing called a one-night-stand, nor the idea of friends-with-benefits. But that isn't what she would categorise this thing Castle seems to have with Meredith. Meredith and Castle aren't a one-night-stand; they were married, have a child and will constantly have to see each other for the rest of their lives. They also aren't a friends-with-benefits arrangement. They aren't friends, if it weren't for their daughter, Kate is confident Castle would prefer to have nothing to do with DFT. So, the only possible explanation is that the shine has worn off of their attraction, at least for Castle. Kate isn't easy; she likes her potential partners to work a little for it, to prove their intentions – so to speak. Perhaps that is old-fashioned in a sense, but she knows she's worth it. She just wants to make sure the men her life are aware of it too.

So she eases back from that precipice. Castle must not be as interested in her as she first thought. Oh, he's probably still interested in her in some respect, but not in the manner in which she was interested in him. Kate wasn't looking for what Castle seemed to be. She put him the friend box and moved on. But he couldn't quite seem to stay in that box; he kept climbing his way out, scratching at that old wall of hers. Just when she was contemplating allowing him to start tapping away at the fortifications around her heart, he goes and comforts Ellie Monroe.

It was a shock.

She had thought they tacitly understood one another, perhaps she wasn't clear enough with him about her responses to him. Kate supposes on reflection that she hadn't been treating Castle any differently, really. And he wasn't a monk. He probably had been gaining release with women all along, just not in front of her (telling her about it at least, except for Meredith). At any rate, she pulled away further from that aspect of their relationship. Perhaps they truly were better as friends and work partners.

If Castle was willing to pursue relationships elsewhere, two to her none so far, maybe he was trying to tell her subtly that he had changed his mind. She was still the 'muse' for Nikki Heat, but no longer the focal point for his romantic interests. Kate truly liked Castle, he was a great friend, a wonderful father and good person, but apparently not going to be pursuing her any further.

She could deal with that. It took her a week or so to reconcile this fact to herself and she was surprised when she felt an instinctive pull towards the new cop at the precinct who helped her train. It was a further delicious pull when he turned out to be a robbery detective. So, after acknowledging Castle's lack of interest and Demming's concerted efforts, without the inanity of Castle's childishness, she accepted his offer of a date.

Had Castle been upset about that? Esposito seemed to think so.

He offered for her to come with him to the Hamptons for the long weekend. She'd said no of course, it was inappropriate when she was dating Demming. But the idea lingered. Perhaps, she and Castle could explore their connection further, perhaps this was Castle's way of saying he was interested, and he wanted to let her know before she fully committed to Demming.

Over one restless night, she thought and thought and pondered, Castle was very much the type of guy she could spend the rest of her life with… and she did want to see where it could go, much more that she was interested in seeing where a relationship with Demming might lead. So she'd broken it off with Demming and was about to tell Castle she wanted to go with him to his beach house when he'd slung an arm over Gina's (second ex-wife's) shoulders and sauntered away.

That had been more than a shock.

That had been like a punch to the gut, she'd been winded and while not humiliated, entirely embarrassed. Another few layers of bricks went up on the wall before she'd felt safe enough to accept Castle back into her life, in any capacity.

She still oscillated between friend and something more. But Castle was clearly with Gina, again. Did the man have some weird fixation with going back to things that obviously didn't work? Like a dog to its vomit, he'd twice (in her friendship with him) reverted back to failed romances. Did he not learn from mistakes? Actually, now that she thought about it, he'd also managed to sneak in some kissing action with Kyra Blaine during that whole 'my friend died the night before my non-wedding' fiasco. So that makes three for Castle and, at the time, none for her.

So while she mended the blatant disregard to her attempt to get closer to Castle, he was off in his Hampton mansion re-acquainting himself with Gina.

Eventually, they reconnected and were partners again, but their romantic prospects were definitely off the table. Kate was sure of that, especially when he returned and was still dating Gina. Perhaps, if their attempt to reconcile had ended swiftly, or at least before he returned, then they might have had a chance but no, that did not occur. They had missed their moment.

So, clearly over the course of the summer Castle had come to a decision regarding their strange will they/won't they aura. It was obviously a 'won't they' kind of situation.

She'd already reconciled the possibility that Castle was gone (romantically) from her life. It had taken a few weeks to truly accept it, but she had, she moved on too.

When she'd gone into her favoured mechanic's to check that weird sound coming from her Harley and run into a gorgeous looking motorcycle enthusiast who'd been interested, she'd said yes to the coffee date. When their conversation turned to jobs and she'd discovered he was a doctor, it just kept getting better. But she never said a word to Esposito, Ryan or Lanie. Which was odd, usually at least Lanie knew. For some reason she didn't really want to share Josh.

But she was serious about Josh, and if not specifically him she was serious about having a serious relationship. Only, events kept inserting themselves into her life. Josh's passion and dedication for working overseas in poor and developing countries was inspiring and wonderful, but with her own passion and dedication for her job it left little time for them to actually be together; which in turn meant that it was difficult for them to progress very far in their relationship. Things were made worse when Castle started seeming despondent. Oh, no to do with her, but to do with his own relationship with Gina. They broke up and Kate could feel his attention zeroing back in on her. It was confusing, especially since she was with Josh and Castle had clearly made his feelings known. Hadn't he?

But somehow they still flirted, not unusual for their friendship; it's how they relate to one another, but somehow that and a stupid idea had ended up in a kiss. Two, to be precise; they don't talk about it. A dirty bomb and a sub-zero freezer hug, nearly dying in one another's arms, and they don't talk about it. She's shot by a sniper, nearly bleeds out on the grass, in his arms, in a cemetery - mere yards from Montgomery's body and they don't talk about it. He holds her close, blood seeping into his clothes, staining his arms and hands, tells her he loves her, and they don't talk about it. She left him for three months, caught up in despair and desolation, trying to learn how to live again, to live with the knowledge that her mentor betrayed her (practically on a daily basis), trying to live with the knowledge that Castle loves her, is in love with her, and they don't talk about it. She doesn't talk about it, about anything, not with Castle, not with Lanie, or her Dad, never with Josh and certainly not with herself. But she wants Castle in her life, she wants more than just his friendship and she definitely doesn't want Josh, even though he was wonderful and perhaps, if she had never met Castle…

But she has met Castle, and she does want him. Only, how?

There is so much that she's muddled up. Thankfully, he's forgiven her for running from him. They are together again, much the same as before only now there's a future, there's a definite something, not quite a promise but an assurance. She wants this. She wants him.

She wants that wall to come down. She wants one day, hopefully soon, to turn to Castle. Rick. She wants to huddle in close, hands caressing each other. Thighs meeting; breathe combining in the same air. She wants to say 'remember those wall I built, well, they're tumbling down', she wants to say 'I found a way to let you in'. She'd like to be able say to him that 'she never really had a doubt' but she had had doubts, many and often. But this last year, he's been there for her, always.

She's showing him more of herself, she couldn't keep her feelings repressed when the bank had exploded, and she'd been so sure he was dead. Hoping against hope that life wouldn't make her walk back outside and have to tell Alexis that her father and grandmother were dead. She'd promised, and for once life had given her a reprieve.

She's not there yet, unfortunately. No matter how much she feels it, that love for Castle, because she won't lie to herself anymore. She loves him and she wants to be with him, but the wall is still there, and she knows she's asking a lot of Castle. Measuring the amount of patience one man could possibly have, she only hopes that there's still some more patience left in that barrel. She doesn't think she could handle it if one day, Castle scrapes the bottom and realises he's got nothing left to wait with.

Still, she hopes, she prays, she holds tight to her faith in Castle, in them, in 'always'.