What you need to know: Story starts around the a few days before the Christmas episode of season 2.

Derek paced back and forth in the lobby of the hospital with two cups of coffee in his hand. He received a call from his mother early in the morning telling him that she was about to board a plane to Seattle. Derek got another call an hour earlier and that's when his mother informed him that her plane had landed. She said she was going to get her luggage and take a cab to the hospital. That's how Derek ended up pacing the halls anxiously waiting.

Addison walked in through the sliding doors and saw her husband walking back and forth. She moved toward him and raised a brow. "Hey, babe. Were you waiting for me?" she asked, smiling just slightly at the thought.

Derek stared at her blankly for a few seconds. He realized that he was standing in a hall at 8 in the morning with two cups of coffee in his hand. He didn't know how to tell her the truth. "I'm waiting for…"

"Someone else." She finished for him without being able to hide her disappointment. She had hoped that for once since her arrival in Seattle her husband was showing affection. "I should go. I've got a c-section in a 20 minutes and I still have to change and give her a pre-op exam." She said before walking away.

Derek's eye followed her until she entered the elevator and the doors closed, no longer allowing him to see her. He felt the familiar heaviness in his chest, it had been there since he agreed to make their relationship work and he didn't know how to make it go away.

"Derek." A familiar voice called from behind him, placing a hand on his shoulder.

Derek quickly turned around and smiled. "Mom!" he exclaimed, wrapping his arms around the woman. After pulling out of the hug he held out the cup of coffee and her and smiled. "Black with one pack of brown sugar...you still drink it like that, right?" he asked.

Carolyn nodded and accepted the cup. "Thank you, Derek. I needed some decent coffee. The stuff they served on the plane was terrible." She said gratefully as she took a sip. "I've missed you, son! It's like you moved out here and forgot how to call me every once in a while so I can know how my only boy is doing."

"I've just been really busy." He answered as they walked toward the elevator. Derek led her into his office and watched as she got settled on one of the chairs in front of his desk.

Carolyn picked up the name plate from the front of the desk and inspected it before smiling at her son. "Derek Shepherd, M.D Head of Neurosurgery and Neurology." She read alone proudly. "My son is the head of his department at Seattle Grace." She set the name plate back down on the desk and looked at him seriously. "But really, Derek, how are you?"

"I'm fine." Derek replied as convincingly as he could.

"Derek, you left your wife, your friends, your career…your home and you moved here. That can't be 'fine.' Talk to me, Derek. I'm your mother, you used to tell me everything."

"There is nothing to tell, Mom. I'm fine. Shi…" he stopped himself from finishing the word. "Stuff happens. I'm fine. I'm doing alright…" but he was interrupted before he could finish.

"Derek." Addison said as she appeared in the doorway. She stopped before walking past the threshold, her eyes fixed on the woman in the chair in front of her husband's desk. "Mom!" she exclaimed in surprise.

"Addison." Carolyn replied with equal shock while staring at Addison as if she'd seen a ghost.

"Addison, what are you doing here? You said you had a c-section scheduled for right now." Derek asked quickly, again feeling the heaviness in his chest.

"I did but then I got paged to the ER for a more emergent case so my resident took over the c-section. I came up here to talk to you because I need a consult for the patient who came in." she answered, still stunned by her mother-in-law's presence. "But she's stable, she can wait a few minutes. What are you doing here, Mom? Why didn't you tell us you were coming?"

"Actually she did tell me." Derek spoke up. "But I haven't had the chance to tell you."

"Oh." She mumbled and awkwardly looked down to the crocs she had changed into for the surgery she thought she had. The beeping of her cell phone broke the silence between them so she checked the page. "Resident is having trouble with the c-section. I've gotta go. I'll come back about the patient." She said before quickly leaving.

"Addison is here." Carolyn stated in shock, staring at her son with her jaw hanging open. "How can you neglect to mention something like that?"

"I don't know! It never came up." Derek replied defensively as he took a seat on the comfortable, black leather chair behind his desk. "Two months after I moved Richard called her to Seattle for a surgery that only she and four other people in the world can do and she brought divorce papers with her but I couldn't sign. I asked her to move from New York and she did so here we are."

"You're still together?" Carolyn exclaimed with disbelief. "You've been together all this time and you never found the right time to mention it? You tell all your sisters about some girl you met and how refreshing it is and it turns out that's all a lie and you're still with Addison!"

"It wasn't a lie." Derek told his mother. "I was with someone else when Addison first came out here."

They sat there in an awkward silence for a little while, neither knew what to say. Carolyn didn't want to hurt her son with too many question. She just wanted what was best for him and for 15 years she was of the firm belief that Addison was not best for her son. She was thrilled when she discovered Derek had left her, he hoped he would finally find someone who suited him better.

Addison had been walking down the hall back toward her husband's office. It had been 15 minutes since she left so she was hoping Carolyn would be gone. She didn't want to be confronted about the affair. She didn't want Carolyn to pretend to be the mother Addison wished to have. She was just about to walk in through the door when she heard Carolyn ask, "Are you happy with her at least?"

Addison froze outside the door. She knew she shouldn't be eavesdropping but she wanted to know the honest answer so she stayed still and quiet.

"I don't know." Derek replied.

"You don't know?" Carolyn repeated. "What is there to not know? Either you're happy together or you're not."

"We're trying."

"You shouldn't have to try to be happy." Carolyn answered. "Do you love her? Addison, I mean. Do you still love her?"

"I don't know." He admitted again with a touch of guilt to his voice. "I'm trying." He repeated.

"You're trying to love her? You shouldn't have to try to love your wife, Derek. Again, either you do or you don't." his mother told him. "And the girl you were with. I believe Nancy said she was an intern. Do you love her?"

"I did. I don't know if I still do. I used to love Addison too but we've got so much baggage and I don't know if I can ever forgive her for what she did. She's not the same person I fell in love with 14 years ago."

"So why are you still with her? Why didn't you sign the papers and move on with your life? You're giving her false hope that she's still got something to hold on to and you're holding yourself back." Carolyn told her son softly. "I never liked Addison, you know that. I didn't think she's right for you. But she's not a bad person…if you look passed the adultery. She deserves to find someone who will understand her and love her better than you are now. And you, you deserve to be happy. You don't deserve to 'try' to be happy or 'try' to love someone and she doesn't deserve someone to 'try' to love her." She paused and looked into Derek's eyes. "Why didn't you sign the divorce papers if you felt this way?"

"I didn't want to be the one to end our 11 year marriage. I don't want people saying I left her. She doesn't get to be the victim. She's the one that cheated, she's not the victim." Derek told his mother. "I didn't sign the papers thinking we'd try for a month or so and she'd realize it's not working and go back to New York to proceed with the divorce. I wasn't expecting her to stick around and put this much effort. And now I don't know if I want her to go or not…"

Addison felt like a knife was stabbed and twisted into her stomach. She quickly moved away from the door and locked herself into a supply closet to let out a sob she'd been holding in. It only took her two additional minutes to collect herself before she wiped away the evidence of her weakness and went on with her day.

Carolyn walked through the halls of Seattle Grace trying to locate Addison's office. She stopped when she saw a small sign beside the door with her name on it. Carolyn lightly knocked on the door and poked her head in when she heard no answer. She saw Addison curled up with her back to the door on a small couch in the darkened room. She hesitated for a moment before calling her name to wake her.

Addison turned over on her back and sat up as soon as she saw her mother-in-law. "Mom." she said, forcing a convincing smile.

"Are you alright?" Carolyn asked, noticing that something was off with Addison.

"Yeah, yeah, I'm fine." Addison replied assuringly. "Richard added me to his team with the intention of building up a NICU that tops every other NICU west of what I had helped create in New York. Let's just say it's a lot more time consuming when you're not a team with 5 other brilliant neonatologists. I haven't slept a full 8 hours since I got here." She added, smoothing making her lie much more convincing.

Addison did not grow up with parents who could tell when she was lie, she didn't have someone comforting her through hard times and rooting her on through achievements. That changed when she became a part of Derek's family and she was grateful for that. But now she knew that she never belonged and that all the affection she'd received through the years was fake.

"Are you sure that's it?" Carolyn pressed on. "You look pale, you're slightly thinner. You are a lot less energetic and happy than I remember you. I just feel like something is going on with you. You can tell me, you know."

"I can't." Addison replied simply. "I'm not ready to talk about whatever it is that's bothering me and I'm sure as hell not going to burden you with being the one to listen to it. I'll be fine. You're here to see your son because you haven't seen him in a very long time and I'm not going to ruin this trip for you."

Hey, guys! New Story :)
The first chapter is very vague, I know you can't really figure out the plot based on what you've read so far but things will get intersting, I promise. At least I hope you guys find it interesting.

Let me know what you think so far and if you're up to it, try to guess what's going going on with Addison.

Oh, AmyHale, you don't count because you already know and thank you for helping me get my thoughts in order for this story.