Okay. So. I don't know if this has been done before but I'm going to try to do this crazy thing. I'm really excited about the potential this story has. I can't promise consistent updates, as I only have another chapter and half written at this point, but I have big plans. I hope you enjoy, and please read and review. Thank you:)

Decisions. No one likes to make them. When we were little, our parents told us that one day, we would know right from wrong, that the right choice would seem obvious, that we would know what to do. Maybe they knew something we don't.

Since she could remember, Addison Montgomery-Shepherd had been sensible. Level-headed. Rational. She'd never had very much drama in her life, she'd never caused gossip and she'd definitely never been a rebel. She was the girl in the front of the class with all the answers. But when she met Derek Shepherd, all of that changed. She became bold, adventurous, maybe even a little reckless. Maybe even a little adulterous… if adulterous was something you could be "a little."

She could handle his leaving; she'd mostly brought that upon herself. She could handle the cheating on his part. She could even handle the fact that he was still pretty obviously in love with Meredith. What she could not handle was the situation that rested in her hands at that very moment. Well, the situations.

In one hand, she held the pair of size 4 black lacy Victoria's Secret underwear that she'd found in the pocket of her husband's tux. In the other was a positive pregnancy test.

Addison didn't know, couldn't explain how it had happened. Fingers still shaking, she walked to the tiny bathroom and dropped the pregnancy test into the trashcan. The big plus sign stared up at her.

She breathed deeply and sat back down on the bed. This was such a mixed blessing. The past couple years she'd been dying to have children with Derek. Any day but today she would have been overjoyed at this news. She'd imagined this moment so many times, but all of them were different from this. She thought she'd be younger, she'd thought she would learn the news on a sunny day; she'd imagined padding down the hall barefoot, still in her pajamas, waking Derek up with a kiss, putting his hand over her belly and whispering, "We're going to have a baby." Addison's heart wrenched in her chest every time she saw his eager eyes, his pure joy…

But that was not reality. She looked at the panties. This was her reality, and it felt like she was drowning. Derek obviously didn't love her anymore, he obviously wouldn't want children with her… and she certainly didn't want him if he didn't want her. God, this was such a mess…

Addison jumped when the trailer door opened. Derek closed it behind him and looked up, straight down the hallway and into the bedroom where Addison sat on the bed.

Slight pause. Sigh. "Hey."

"Hey."

Another sigh. He looked tired, exhausted, sorry. "There's something I have to tell you, Addison."

She held up a hand in protest, the hand that still held the pair of underwear. "I think I know what you're going to say."

Derek let out a big breath and sat down next to her on the bed. "Oh…"

She took a shaky breath of her own, finally finding the courage to ask the question that had been on her mind ever since she'd met a certain intern. "What is it about her, Derek? What is it about Meredith Grey that I don't--"

"Addison--"

"I want to know, Derek. What is it that makes you love her and not me?" She looked pleadingly at her husband, desperate for an answer. "Is it because she's younger, is that it? Do you not like that I've gotten older? I mean I know I'm not as thin as I used to be, but--"

"Please, just listen--" he tried to begin.

But Addison was confident now and she wasn't going to let him stop her. "No, Derek. You listen. It's my turn now, okay? My time to talk." He fell silent. "I gave up my life for you. Twice. I was the one who didn't want to get married straight out of med school but you insisted. And I thought 'When am I ever going to meet such a great guy again?' So I married you. And, honestly, I don't know whether or not I regret it. I don't even know if I regret starting all over again--again--by following you out here. But the point is, whether or not I wanted to, I did it. I gave up everything for you, Derek. And I felt like… you didn't give anything. When our marriage was in trouble in New York you just sat there. You didn't try to make things better, you didn't want to go to counseling, you didn't--"

"I didn't sleep with your best friend, Addison," Derek interrupted angrily. "But you slept with mine."

"Do you know what it feels like to be ignored every day of your life by your own husband?" Addison retorted in disbelief. "And then when someone finally shows some interest in you… do you have any idea how good that made me feel?"

"We had problems," Derek admitted. "But what were you doing to help them? Avoiding me, spending the night with friends without so much as a note to tell me where the hell you were?"

"Don't you dare make me the bad guy here!"

"You don't know how it fe--well, actually, you do know. You do know how it feels to find out your spouse is sleeping with someone else. But the way it felt for you was not the same way it felt for me. You slept with Mark to get noticed. I slept with Meredith because I was alone, hurt and because she made me feel alive again."

"Oh, so two wrongs make a right? I sleep with someone, you sleep with someone, we're even? Marriage doesn't work that way, Derek," Addison argued.

"You're right," he snapped. "It doesn't work that way. It was my mistake to try to fix a relationship that was already so broken."

Addison had no answer, knowing that they were now getting down to the root of the problem. This was it. This was the part where they told each other they didn't want to be together anymore.

"So," Derek began, "I came back tonight to tell you that I had sex with Meredith again--" She flinched, even though she already knew. "--and that I think it's best for both of us if we get a divorce."

She nodded slowly, staring blankly ahead. "Okay… okay."

He sighed in exhaustion. "I'm sorry you had to find out this way," he said, gesturing to the panties on the bed.

"Yeah," she said quietly. "Me too."

Derek walked down the narrow trailer hallway to the bathroom. Addison shut her eyes and breathed deeply. She heard the bathroom door close, she heard the toilet seat go up, she heard the flush of the toilet and the water running in the sink, and then--silence. Something about it was unsettling, not right… She heard the door open but didn't want to look.

"Addison."

She breathed. In. Out. She opened her eyes and Derek stood there holding her pregnancy test. His face was blank. There was nothing in his eyes. He looked older.

She couldn't find any words but, "I'm sorry you had to find out this way."

X

Three hours later they sat facing each other on the bed. "So you want to keep it."

Addison nodded firmly. "Yes. Yes, I am sure about that. I've wanted kids with you for a while." She sniffed and reached for the box of Kleenex that sat between them. "But Derek? Please be honest… do you want to keep it?"

His answer was so immediate it almost sounded rehearsed. "I want what's going to be best for you and the baby."

"Yeah, but what do you want?" she asked. He hesitated and she said, "Look Derek, I need you to be honest with me here. If you don't want to be with me, I understand. That's fine. I just don't want someone who doesn't want me."

He sighed. "Addison… I don't think I can give you what you want anymore. I love Meredith. But…" He nodded slowly. "But I don't want my child growing up without a father. I am going to be there for you through this and I am going to be there for this baby."

Tears leaked out of her eyes. "So you don't want a divorce?"

"No. I'm not going to be the guy who abandons his wife when she gets pregnant."

"But… what about after this, what about after the baby's born, I mean, are we going to stay together, are we going to separate but still see each other for his sake? There's so much to think about here, Derek, and I just want to make sure you're making the right decision."

"I…" he faltered, his eyes stirring. "Okay, I need to think about this. I need…"

"Just think about it. And let me know."

Derek nodded. "I will do that."

Addison smiled. "Okay."

You always think that you know what's right and what's wrong, that in the heat of the moment, you're going to make the right choice. But as you get closer and closer to that fire, the lines between right and wrong, good and bad, begin to blur, and suddenly you find that you have no idea what to do.