Chapter 1

"Okay so everything is charted and ready to go. Is there anything else you need, Dr. Shepherd?", Lexie asked as she handed him Mr. Turner's chart.

"No I think we are all set. Thanks, Lexie", Derek replied, "Have a good night."

"Thanks. You too."

Lexie was practically dragging her feet as she walked through the door of the apartment. It had been a long day and she was exhausted. After two craniotomies and countless pre-op and post-op workups, all she wanted to do was relax and do nothing. She sighed as she dropped her bag and her worn out body on the couch and slowly drifted to sleep.

About 2 hours later, Lexie woke to the sound of the front door closing. She sat up and saw Mark hanging his coat.

"Hey, how did it go?" she asked. He had a major skin grafting operation that he had been nervous about for days.

"It was touch and go for a while, but we were successful. How was your day?" Mark said.

"Tiring. Same old stuff, you know?" she responded.

Things had been kind of awkward between Mark and Lexie since he returned from his trip to LA. She wasn't sure if maybe she had unintentionally done or said something, but one thing was clear, something was definitely up. This wasn't the guy she knew before, cold and distant, like he opened up to her just to close her off again. Fed up of the days of constant tension, Lexie asked the question she had been holding back for days.

"What is wrong?" Lexie asked calmly.

"What are you talking about?" Mark responded.

"You've been acting strange lately. When I talk to you it's like your mind is somewhere else." she explained.

"There's just a lot of stuff going on lately. Lots of stuff." he told her.

Lexie rose from the couch and walked over to where Mark was standing and wrapped her arms around his neck.

"I'm sorry you're so stressed out. But you can talk to me about anything. I'm here for you." she reassured him. "There is nothing you can't tell me."

Actually there was. Mark decided that this was the time to come clean. If she really loved him then she would find it in her heart to forgive him.

"I have to tell you something." Mark said in a serious tone.

"Uh-oh. That sounds bad." she replied.

"Can we sit down please?"

Lexie and Mark made their way to the couch and sat down. There were a few moments of tense silence before Mark continued.

"Something happened in LA." Mark said

"What do you mean? Something happened with Sloane?" Lexie asked, concerned.

"No, no. Sloane is fine, she's on her way back to her mom now." he said.

"Then I don't understand." she said.

"Well, um…you see…" he stuttered.

"Mark, just spit it out." Lexie urged.

Mark sighed, "I slept with Addison."

Stunned, Lexie sat and soaked in what just happened before responding.

"What?" she lightly whispered.

"It just happened. I never meant to hurt you." Mark started.

"Please don't do that." Lexie started.

"Do what?" Mark asked.

"Give me the long, drawn-out, explanation. I don't need to know. I don't want to know. I know enough." Lexie said, on the verge of tears.

"Lex, please" Mark tried.

"I have to get out of here." Lexie said as she slowly got up, grabbed her bag and made her way out the door, leaving Mark alone in the darkness of their apartment.

Lexie got in car and drove to the only safe haven she knew, thoughts running rampant through her mind. How could he do this to her? She thought he had grown, evolved. Wasn't she different? He sure had made her feel like she was different, the only one who truly understood him. But maybe there is just one problem, she isn't Addison. Addison had always been a sore spot for Mark and Lexie made a habit of never bringing it up as to avoid causing him more unnecessary pain. He insisted they were ancient history and that he was completely devoted to this, here and now, with Lexie. So there was nothing for him to hide right? Wrong. Apparently she had been wrong all along.

Lexie parked her car and made her way to the familiar front door. She hesitated but reached out and rang the doorbell. A few minutes later the porch light lit up and Meredith sleepily opened the door.

"Lexie?" she asked with a confused look on her face.

"Hey, I'm so sorry, but I didn't know anywhere else to go." Lexie said.

"No, it's fine. Come in." she gestured for Lexie to enter.

"What did he do?" Meredith asked.

"It's a long story. Can we talk about it tomorrow?" Lexie pleaded.

"Sure. No problem. You can crash in my room. Derek is on-call tonight." Meredith replied.

"Great. Thank you" Lexie said.

"What are big sisters for?" Meredith said with a giggle. "Come on. It's late. Let's get some sleep."