A/N: This is a oneshot for now. I am pretty sure it will be because of how it ends…and also because I am working on Just an Egg and I have plans for another fic after that one. But who knows, I could come back to this. ADDEK. Because, seriously, who doesn't love the McMarrieds?

Summary/Disclaimer: It's about the affair. Starts out the night of it. Ends a bit after that. I don't own Grey's Anatomy…Shonda does and she does a right well job of screwing it up. (I swear I'm not bitter) And the title of this is a song by The Police. So not mine either.

xxxxxxxxxxx

Derek entered the house with his key. It was late; he had just spent five hours on a patient who had died in the end. He was discouraged and depressed. He didn't want to fight with Addison, but based on the cold stares he had gotten at breakfast for sleeping on the couch the previous night, it was inevitable. The house felt different. It was probably due to Addison's cold temperament.

He made his way up the stairs. At the top of the stairs, he stepped on a jacket. It wasn't his. It was blue, and a size or two larger than what he wore. His mind flashed to the bedroom door. It was shut, but he could hear it. He could hear the sounds inside. He squeezed his eyes shut and walked forward.

He flung open the door and saw Addison's nails in another man's back. And not just any other man. It was his best friend. It was Mark.

Addison saw him and fell back into the bed, grabbing a shirt from under Derek's pillow and slipping it on, tears welling in her eyes as the realization slapped her in the face. Mark quickly stood up, grabbed his pants, and left.

Derek stared at Addison. She stood up and ran over to him, looking at him.

"Derek, say something."

"How the hell could you do this to me?"

"Derek, I'm sorry."

Derek didn't care. He strode around the room, grabbing clothes from the dresser and her makeup and shoes. He grabbed the sheet off the bed.

"Derek, please. Wait. Derek. It was one time. I know that's what everyone says. I know that's what always gets said. But he was just here…"

"You screw my best friend and all you can say is 'he was just here'?"

Addison felt tears cascading down her face but she didn't care. She looked at her husband, the love of her life, as he stared angrily and hurt at her. She couldn't believe that she had slept with Mark. She didn't want to believe it. But it was true.

"Out."

"What?"

"Get out of my house." Derek's voice was raised.

"No. We do not quit. I'm standing my ground. We do not quit."

Derek strode over to her and picked her up, forcing her outside with her clothes. She banged on the door, sobbing in the rain, until Derek let her back in.

"Let me show you how sorry I am, Derek. I'm so sorry."

She hugged him and tried to place a kiss on his mouth, but he pushed her away.

"I can't look at you. I look at you and I feel nauseous. I'll go. You stay. I'll get my things later."

Derek looked away sadly. Addison felt everything inside her crash. She spoke softly, tears flowing. "But we're Addison and Derek. If you leave now…if you leave now, we'll never make it. If you leave now, we'll never get through it."

"We're not Derek and Addison anymore."

Derek slammed the door behind him. Addison fell back upstairs and into bed. She didn't move for days. She didn't feel anything physical. All she could remember was Derek's face. His disappointment. She didn't feel hunger or thirst. She just wanted to forget.

xxxxxxxxxxx

Derek was able to avoid Addison. He was able to avoid the Brownstone. Hell, he was even able to avoid thinking about the situation. He pushed himself into work for the next few days. Sometimes, his mind would flit to the topic but at that point he'd just throw himself back to what he was doing. He went to the bar after he had caught them and ordered a drink. And then another. And another. He had spent the night there. Recovering.

And here he was, a week later to date. He was surviving. He didn't know when he would have the courage to draw up divorce papers, but it would be soon. He just couldn't do that. Yet. He had had his heart crushed by Addison and Mark. Addison, the love of his life; and Mark, his best friend. Together. In his bed.

He shuddered and wandered down the hall to an on-call room, where he planned to catch a few hours of sleep. As he approached, he heard people inside, and peered in the window. Mark and one of the nurses were lying naked in one of the beds. Derek quickly walked away and felt conflicting emotions wash over him. He felt angry, as Mark didn't seem to care about Addison. But he also felt ruthless, and wanted to tell Addison. To crush her.

And so, ten minutes later, he was in a taxi, going back to his house. He would get his things, but he would also break the news to Addison. To break her just like she had broken him. He opened the door with his key, noting that most of Addison's clothes were gone, probably taken. The remaining ones were so damaged nothing could be done. And it gave him small satisfaction.

He stepped into the bedroom, and he saw Addison curled up in their bed. He knew she was awake, but for his sake, she was pretending to sleep so that he could grab his things in peace. She looked so small and pathetic. Her eyes were red and tears were flowing, but she had stifled them for now.

Derek stepped into the bathroom and tried to clear out his cologne and toothbrush but he couldn't. Addison's things were exactly the way they had been the night before…before Mark.

He stepped into the closet and Addison's outfit choices were crumpled on the floor exactly as they had been a week ago. He had seen her clothes still out in the hallway. By the looks of it, she hadn't left this bed ever since Derek ran…and that made it a week. Had she eaten? Was she okay?

Derek shook his head to rid himself of the thoughts. She had cheated on him and now he had his revenge. Mark was now sleeping with another nurse. She shouldn't have expected anything different.

But this was his wife. His wife who, for the better part of the last few years, he had ignored. Not completely. But enough that it was painful. She was still wearing his shirt and her makeup was smeared all over the pillowcase. She had to have skipped work for this breakdown, and he knew she had had an important surgery the day before. But based on the state of her, she hadn't gone.

All of these things broke Derek's heart more than her sleeping with Mark. Seeing his strong wife, his independent wife, like this was enough to kill him. She was hurt and damaged. He rarely saw her like this. And it had never been this bad. Never a week without eating, without putting on makeup. And Derek knew it was her guilt and his fault that caused this. And he wanted to fix it.

Derek slipped off his shoes and crawled into bed next to her. She tensed visibly as he started stroking her hair.

"I'm so sorry, Addie. I'm so sorry for what I did that night and what I didn't do but should have. I'm so sorry I left you here like this, never knowing if I'd come back or not. I'm so sorry."

Addison's silent sobs were racking her body and Derek just pulled her closer. She stifled a tear and tried to breathe normally.

"Derek I-"

"Don't talk now. I know you want to, but don't. Just let me talk. Right now. Have you eaten? Had anything to drink? At all?"

Addison shook her head. Derek felt his heart sink.

"We need to get you some food. I'll make pancakes. Come, downstairs, and we'll make pancakes. I think we have butter and syrup. You can have some coffee while I make them."

Addison wiped away tears and stood up for the first time in days. She hadn't eaten, she hadn't been hungry. She hadn't had to use the bathroom, because there was no food in her. For the past week, she had thought over the failed marriage she thought she had and her mistake. It pained her to remember such a mistake. She had never meant to sleep with Mark. She just wanted to feel something instead of numb. She had wanted Derek to care.

She sat down in a kitchen chair and watched as Derek made a pot of coffee and got out eggs, butter, sugar, and flour. He had always been more of the cook than she had. He said nothing as he threw the leftover Chinese in the trash, knowing it was the meal she had shared with Mark. He threw a bottle of wine in there as well, noticing it was almost gone.

In five minutes she had a cup of coffee in front of her. She drank it quickly, her throat dry and parched. In twenty minutes she had golden pancakes in front of her. Derek sat down next to her with his own plate and took a bite.

"Addison, I don't want to talk about it right now. I just want to make sure you're okay. So, don't try to get me to for a while, please. I am terribly sorry for what happened that night, and I hope you are too. I hope you just made a mistake and that it really was the only time. I hope that you don't…love him. But please, let's just sit for a while."

Addison nodded. She took a tentative bite of her pancakes. They slid down her throat. She tried to smile. She tried to at least stop crying. But it wasn't working. She had been on such an emotional rollercoaster lately that crying was second nature. The tears just slid out.

Derek kept subconsciously touching Addison's hair, her hands, anything. He just wanted her to be okay. He wanted her to be the strong Addison he knew, not the broken figure in front of him.

As Addison finished her pancakes, Derek suggested she take a shower. Addison complied and strode upstairs to take one, Derek following. He stripped the bed of the sheets and threw them in the wash. He cleaned up around the room, including the clothes that he presumed Mark had ripped off. He shuddered as he thought of Mark touching his wife. The image of Addison's body pressed to his made his head spin.

xxxxxxxxxxxx

Addison stood in the shower, letting the water wash off the past week. She felt tears strip off her body with the mascara and perfume.

Addison sat on the couch with Chinese food watching Pretty in Pink and heard the phone ring. She didn't pick it up.

"Hey, Addie, it's Derek. I have a surgery and won't be home tonight. I'm-uh-sorry."

Addison sunk lower on the couch. She wanted Derek home. She wanted him to sit watching movies with her. She just wanted him there. She picked up the wine and poured herself another glass. And then she heard a knock on the door. Mark stood at the door.

"Hey, Addison. Derek told me that you would be home alone tonight and to come over, since you had the day off."

"Oh, hi."

"What are you watching?"

"Pretty in Pink."

Mark smiled. "Can I come watch for a while?"

Addison shrugged. "Sure."

Addison watched the movie and kept pouring herself wine. Mark watched her put more and more alcohol into her body but didn't do anything to stop her. Addison had an unbelievable tolerance for alcohol. She might be shaky, but Mark knew her senses were still just as sharp. As the credits rolled Mark stood up to go. Addison stood up unsteadily. Mark grabbed her arms as she fell, pulling her up. Addison stared into his eyes. Large and beautiful, like Derek's. Addison couldn't stop staring at them. She wanted to be loved. And maybe, maybe Derek would find them. And maybe he'd care even if he was angry. Getting anger from him would be better than nothing.

She leaned in and kissed him. She pressed her mouth to his and slipped her tongue into his. He kissed back eagerly. He had waited for this for so long. Fourteen years. When she had agreed to go out to dinner with Derek in Med School. Not Mark. Derek. She unbuttoned the buttons on his shirt. She slipped his belt off as he ran his hands under her shirt. He didn't once stop to ask her about this. He knew if he did anything she would remember it was not Derek. That it wasn't her husband. That everything was wrong.

She led him upstairs, stumbling. He slipped off her shirt and they fell into her bed. The bed she shared with Derek. She moaned Derek's name. Mark tried to pretend it was his.

And then Derek had come home. And he had noticed. He had gotten angry. And he had left.

Addison felt all of those emotions again and wondered why she had ever done this. She finished out her shower and stepped into her bedroom.

Derek felt his breath catch as Addison stepped out of the bathroom, a towel wrapped around her middle but water dripped over the rest of her, shining her skin.

"Oh, God, sorry. I just needed some clothes."

"Addison, it's okay. I've seen you like this plenty of times."

Addison blushed. "Yeah, of course."

Derek left the room and waited until she came out in grey sweatpants and a white T-shirt. Her hair was still damp and she hadn't put any makeup on. And Derek thought she looked beautiful.

They sat downstairs on the couch and turned on the television to give background noise. Addison was twisting her hair nervously. Derek stared in front of him.

"I'm sorry, Derek."

"Yeah."

"I didn't want to. I had a buzz of alcohol and Mark was standing there. Reminding me of you. I knew it wasn't you. I wanted to feel something though. And you weren't coming home. And I was angry and sad. And Mark was just there. And I kissed him. I know that hurts to hear. I won't go into detail. But you need to know that I kissed him. Even if you…even if you hate me, I started it. And I am so sorry. I don't know why you're here, being so nice. I know you're sorry, but God, what do you have to be sorry for? I mean, you reacted normally, like any husband would. You have nothing to be sorry for."

Derek grimaced as she spoke. She had kissed Mark. Sure, he had probably elevated it from there, but she had kissed him. Not the other way around. Not the way he had hoped against his will for.

He knew Mark was an ass and manwhore but he would never overstep the boundary between marriage. He knew that it was Addison who would've had to do it. And she had. She had and it made him feel horrible.

"Addison, I'm sorry. I might have acted like any normal husband would, but I don't want to be just any husband. I want to be the love of your life. You are still mine. But I don't know if I can be yours anymore. I shouldn't have just walked off like that. If I was really the love of your life, I wouldn't have."

The silence between them was massive. Colossal. Finally, Addison spoke.

"Why didn't you just grab your things today and go?"

"Because I saw you. Crumpled up. And I couldn't bear seeing you like that. It broke me more than finding you with Mark. More than anything ever could."

Addison squeezed her eyes shut so he wouldn't see the tears forming in her eyes.

"Oh, Addie, come sit on my side of the couch."

Addison looked up and saw Derek holding out his arms. She slid over into them and he pulled her into him.

She looked up into his eyes. The right eyes. The deep blue. She took a deep breath. "Can we make it through this?"

Derek nodded. "We can make it though this. We can."

"How long is it going to take you to forgive me?"

"It will take time. But how long will it take you to forgive me for being so absent?"

"It might take time."

Derek hugged her closer. "Then we're going to make it after all."

xxxxxxxxxxxxxx

A/N: So it was a longer oneshot. It ended in a place where…it could be the end. But I could pick this up again. I'm very content though, so unless I'm really looking for a new story, this one is done.

Tell me what you think.

And no, I haven't given up on Just an Egg. I'm just getting there. Writer's block. Sue me. A few days and I'll have it.