The TV Show Castle and all the players belong to Marlow/ABC/Disney.

I do not own them. I wish I did, but I don't

For my loyal fans. You know I normally do not do Angst. Sorry
This one is Angst. Lots and Lots of Angst

It gets better

Remember the rules. My stories are based on legend but are A/U
The story begins in season 3 around 'Countdown'

Castle takes a blanket from the ambulance and wraps it around himself and he walks toward a similarly blanket covered Kate Beckett who is leaning against a police cruiser. As he approaches her location, he sees that she is staring, not at Castle, but her look is very affectionately directed at Doctor Motorcycle Boy who is still waiting by the ambulance.

"So he came back" Rick says as he leans on the car, next to Kate

"Yeah he did" Beckett responds without taking her eyes off the physician

"So what does that mean to you" Rick asks Kate. He is afraid of the answer that he knows is coming from her

"It means we have a chance" Her response with a higher pitch in the tone of her voice when she spoke the last word 'Chance'. There is now an element of hope in her for her relationship to bloom with Dr. Davidson

Wishing against hope that her answer was not what she just said, Richard Castle's heart sinks into his belly. He knows that this will be the end of any possible chance he had with her. He must now make his choice about what he will do now moving forward

During the last few months, he had been building up the courage to tell her how he feels.

He tried to get her to come with him over last summer and spend a couple of weeks relaxing in the Hamptons, but she was dating Detective Deming so Castle gave up and went with his ex wife out of desperation to not be there alone. At least with someone else with him there, he would have something, anything to take his mind off of Katherine.

But everyone knows how bad that turned out.

After he rejoined the team at the precinct and had again separated himself from his publisher and ex wife, he had the opportunity to hook up with the beautiful actress who would be playing Nikki on the big screen, Natalie Rhodes. But again he felt it was not the right thing to do. He passed on his chance with Natalie Rhodes all the while waiting, because he felt like Kate was the right choice.

The undercover kiss he placed on Kate's lips while attempting to rescue Esposito and Ryan was almost more than he could stand. He wanted to tell her what it really meant to him, but even then she was already committed to the medical professional that Castle has really grown to dislike, so he chooses to not push.

Castle watches and loves her from afar and he hurts for her each and every time the good doctor chooses the job over Kate. He sees that she is pulled back into a dark funk that only he seems to be able to bring her out of.

Then earlier in this case while they were in the isolation tent and she began telling him how she felt like she took second place in the doctor's life every time he went away to help save the world

"I wish I had someone who was there for me and I could be there for him and we could just dive into it together"

Again Rick tried to get the words to come out that he wanted a chance to put her in first place in his life, but the technician arrives too soon and broke the train of thought and told them they could leave.

In the freezer he thought he heard her say "I want you to know how much I lo."

What word was she going to say that began with the letter "L"

So now, standing outside recovering from the hypothermia they experienced in the freezer, Rick realizes he has no chance at all with Kate. She wants the relationship with the handsome doctor instead of him.

Rick uses this time to decide. He makes his decision. He will not under any circumstance get in the way of her happiness. After they complete the case before them, finding the nuclear materials, he will move on down the road. He will move out of her life and let her find the love she deserves. Even if it is with the doctor, or the detective, or the FBI agent, or someone other than himself. He will get out of her way and let her have her dreams

As Castle watches Dr. Davidson walk their direction, he decides to step away so they can have their reunion. Rick movers over near Agent Fallon with homeland security to allow the couple some time alone.

"When I first met you two, I thought you were together" Agent Fallon remarks

Castle looks toward the couple now huddled together and with all the strength he can bring to bear replies "No, we're just friends" It is what he cannot bring himself say that speaks volumes

Agent Fallon walks up to Detective Beckett "Can I see the two of you?" pointing away from their current location

"I guess I am going to need you two to help after all. What can you tell me about the bomb?"

The city wide hunt for the device brings Beckett and Castle into what will be ground zero.

Beckett begins to describe what her and Castle have discovered in the white van and why they believe that this is actually a home grown terrorist and that the family is being framed to make it seem like a foreign attack.

Agent Fallon tells Beckett and Castle to go after the van and try to find it.

Once located, Beckett uses her police cruiser to pursue the van and force it to pull over. After convincing Nazihah that the police had rescued her son she let Castle and Beckett try to disarm the bomb in the rear of the van

Once again Richard Castle and Kate Beckett find themselves in an impossible position. They are facing a dirty bomb ready to explode completely vaporizing the two of them but also rain nuclear fallout all over a large section of Manhattan leaving it uninhabitable for decades to come.

The pair both realize that they will not escape this event alive. They will die but they will be together. Looking painfully into each others eyes, Kate speaks one word. His name "Castle" Her voice filled with sorrow. Possibly indicating her regret for allowing what is about to transpire without ever opening up the truth buried deep within her.

Rick looks at Kate with equal fear, then grabs all the wiring to the device and without conscience thought pulls all the wires apart at once.

Neither believes that they are still alive. The look at the device to see the timer expired and they are both still breathing. They embrace like two lovers who have just been brought together for the first time. Then break apart in celebration

After all the official paperwork has been completed and the team is settled into the conference room to decompress, Homeland Agent Mark Fallon brings the pair together again to thank them. Once the congratulations are over, and Beckett and Castle are left alone. Rick tries one last time to gain the courage to say something to Kate. Anything!

Rick begins his statement

"I was thinking…" But before he can bring his thoughts to mind, he sees, over her shoulder, the approach of Kate's lover. A man that Rick knows he cannot compete with.

"I think I should go home. Get some rest. Goodnight." And he turns to walk away.

"Goodnight?" She responds with a tone of question in her voice

Kate did not realize that what brought the halt to Castle's statement was that Dr. Davidson was, at this very moment, walking up behind her. As this fine man of medicine pulls her into a hug, she watches her downtrodden partner step into the elevator. He leans his head to the back wall. She can see that his eyes are filled with defeat as the doors to the elevator close.

Beckett knows that something is different. This time he did not say he would see me tomorrow. He said goodnight. Like there was not going to be a tomorrow

She does not realize that this is the very moment he has decided that this thing between them is hopeless and he is defeated in his desire for them and therefore "This is over. He is done…"

For them, there is not going to be a tomorrow.