This wasn't how it ends.

Not standing alone in his kitchen while the love of his life walked away.

He didn't wait four years for her for it to end this way.

Castle moved quickly, tracing the steps that his wife took only moments ago. He paused in the hallway, his eyes scanning the form of Kate's body as she stood in front of the elevator, shoulders hunched. "No." His voice reverberated sharply off the walls and Beckett tensed before turning around. "You don't get to walk away from me, from us."

"I'm not-"

"Yes, you are." He ignored the tears that shined in her eyes and took a step closer to her. "You're ignoring me and lying to me and now you're just going to leave? No. I want to know why. Why are you throwing everything we have away for this?"

"I want you safe, Castle. Almost everyone who has been a part of this is dead! I want you safe." Her voice was fortified with determination.

Castle took another step towards her. "And yet you are still running at this! I am safe, Kate! We are safe when we're together!" His voice rose. "Why can't you see that? Together, we can get through anything! When we're apart, that's when we're vulnerable." Beckett stayed quiet, her jaw tense with fear and anger. "I can't keep doing this, Kate. I can't keep waiting for you to be in this."

"I am in this!" She cried out.

"Are you? Because it doesn't seem like you are. You didn't want to start anything with me because you wanted to solve your mother's murder. Then you couldn't decide if I was serious about you, even though I was in love with you for a good two and a half years before we even got together! You moved to DC for a different job. Hell, you didn't even move in with me until after we were married! And now this? You're chasing after a ghost, Kate."

Beckett moved forward, putting them toe to toe. "I am in this! I am trying to stop a man who has a target on my back! I don't want to keep living a life where I'm constantly looking over my shoulder, wondering if I'm going to take another bullet to the heart or have my car blown up on the way to work. I don't want to have to worry about whether or not our kids are going to be safe because I'm their mother and psychopaths and senators have a thing for me! I want to be able to grow old with you and live with you and love you! I'm not doing this to hurt you. I just want us safe."

His hand grasped hers tightly. "I-" A piercing siren broke the moment and Castle turned quickly. "Shit!" He ran back into the apartment, smoke filling the loft as Beckett followed him. The pan with the now burnt smorelette was in the sink, cold water running over it to stop the tiny flames that licked edges.

"Castle?" She called tentatively.

Slowly, he looked up from the sink. He looked so broken, his eyes haunted with heartbreak. His hand extended towards her and she grasped it. Castle pulled her to him, an arm around her waist and a hand buried in her curls. "Please don't leave," he whispered into her ear. "I need you, Kate, so much." She closed her eyes to stop the tears from falling.

"I need you safe, Castle."

"Never safer than when I'm with you," he murmured. "Tigers, freezers and bombs aside." Kate half-laughed, half-sobbed into his chest. "You are it for me, Kate. I don't want to miss any moments with you. If this is all we have, just these few moments, I'm okay with that. I'd rather go out fighting by your side than spend a night without you in my arms." He felt the hitch in her breathing as he tilted her chin up. "So please, don't leave."

Kate shook her head as tears fell. "I love you," she whispered fiercely before capturing his lips.

"I'm with you, Kate, til the wheels fall off."

I wrote this initially in anger, but the more I went on, the more I understood why she did it. I'm more mad that Castle didn't go after her. I may polish this up later.