A/N: the greater part of this fic was written in December 2009 to explore some speculations that were going around then. I recently went back to it and added a few hundred words at the end and, of course, now things have moved on a lot on the show and it is pure (back-dated) AU. So it might be a little late to post this, but . . .

"Mark is," Derek smiles the sort of smile he gives patients he's about to tell to prepare themselves, "complicated. Give him time, Little Grey."

His eyes soften (she has to steel herself not to get sucked into the sympathy) and it passes through Lexie's mind that this may be the single most respectful statement she's ever heard Derek make about his best friend. But it's eclipsed, quickly, by something close to irritation and closer to despair. She can't define exactly what, though, because, for the last eight weeks, emotions - happy, sad, indifferent – have bled into one another without distinction or breathing space.

She nods, as though he said something wise and helpful and kind. But it's all surface and, in reality, he's shutting her out. Just like Mark.

They've known each other for thirty years. She's only Little Grey - naïve and stupidly hopeful about a relationship everyone (even her, really) knew was doomed from day one. In the wake of the last eight weeks of grinding apathy, maybe she should just give in to the implication on Derek's face.

(Although there's a little revenge, of a kind so screwed up and self-flagellating she couldn't tease it apart if she wanted to, that she knows Mark slept with Addison when he was in L.A. and Derek doesn't.)

The cell she's been keeping by the bed just in case he calls rings shrilly, rousing her from early morning sleepiness.

"Mark," she breathes, then waits for the familiar, low vibration of his voice. Last night, when he called her, he was hopeful, said Addison was hopeful. Last night, he told her he loved her and thanked her for spotting Sloan's symptoms in time.

There are no words at first, though, just the sound of him clearing his throat; and she stiffens, sits up in bed almost rigid, knowing what's coming but dreading it all the same.

"Mark?"

"Sloan died."

"I'm so sorry," she whispers. "The baby?" she dares, hoping for better news.

Silence again.

It tells her all she needs to know and she finds herself cradling the sleek black and chrome rectangle in her hand as though, somehow, her touch could reach him. "Addison couldn't . . .?"

"No."

I'm . . ." But sorry really doesn't cut it, especially when it's repeated. She remembers too well being on the lonely receiving end of condolences and resolves not to put him through that. She just wishes she could touch him, hold him. (He's done it for her so many times.) "Mark," she says softly. It's all she has to offer until he comes home.

"I'm staying in L.A. for a few days," he says, voice emptied of any meaningful expression and all the more bleakly eloquent because of it.

Then he hangs up the phone.

For a moment, she stares at the little screen, disbelieving, telling herself it's a technical error, and her fingers begin the process of calling him back.

But her heart is not in it. It knows better.

His life has imploded and, instead of wanting her, he's closing down behind a monosyllabic phone call, taking refuge in a strange city with a woman who never fails to damage him.

He's grieving, she tells herself. In shock. He just lost his family. She knows how that feels.

He's grieving, she tells herself again, emphatic inside her head as she remembers her mother, remembers George, most comfortingly remembers the hours when her father needed a liver when she forgot to tell Mark she was planning on being his donor.

Grief makes you forget. She gets that. (At least, that's what she tells herself.)

"How did the skin graft go?"

"Fine." Mark doesn't look at her (of course). Just stares at the tuna salad sandwich she convinced him to buy, until he decides (as much as he decides anything these days) to reject it in favor the large cup of strong, black coffee that was all he really wanted.

"I wish I could've scrubbed in." Her cheery voice grates even on her nerves, so she gets it when he barely suppresses a grimace. But this is her self-imposed role. Forgiving; loving; there for him. "Your skin grafts are incredible."

He laughs softly through his nose, without any trace of humor, pride or pleasure. "It was a second degree burn," he says. "I've fixed them before, I'll fix them again. Hell, you could've done it."

She overlooks the implicit slight. (She's becoming used to them, actually.) "What do you have this afternoon?" she asks.

He studies his cup, then shrugs. "I'm cancelling," he mutters, finally raising his eyes to meet hers, clearly ashamed but defying her right to question him. "I need to get some sleep."

"Do you want me to -?"

"No."

For a split second, she feels the rejection in her stomach as an actual, sharp pain. Then guilty relief floods her: she's getting an afternoon off from him.

"Well, I'm scrubbing in with Bailey," she says, keeping her voice even and kind (not rushed with the desire to get away; not letting out the tightly suppressed scream that lies beneath each genial word). "I guess I'll see you at home."

She stands and picks up her tray. Mark nods. There's a beat while she hopes a little (because it's what she does, even against the odds and even though she kind of hates him right now) and then she half turns away.

"Hope it's a good surgery," he says in a voice so low she can barely hear it. When she turns back, he's looking at her, forcing a smile.

She smiles back. "Thank you," she whispers, because that's all her voice will do, then adds a stunned and extravagantly misplaced, "I love you."

His weak smile fades instantly, lost in the confusion that covers his face. "Lex, I . . . "

Of course, he doesn't say I love you back and, after a few seconds, she turns and walks away.

"I'm not in the mood, Lexie." Mark rolls over on his side and faces away from her, sighing so deeply it's like a groan of pain.

"I could just . . . I could hold you." She winces at the clumsiness of her words. She would rather just reach for him, but she doesn't have the courage. "Or you could hold me. You haven't—"

"I slept with Addison."

Lexie knew that. She guessed, from the way he told her was staying in L.A.; from the way he hugged her at the airport and it didn't feel like him. She excused him (forgave him, probably, she thinks) on the grounds of mourning. But it required the unspoken arrangement: him not telling, her pretending not to mind. Now, confronted out loud with the words, the betrayal crushes her as her rationalizations shatter.

Sex is what Mark does – to celebrate, to forget, to love, to hurt, because it's 6 a.m. on Monday. And Addison was there and he was desperate.

She gets that.

But she doesn't get the loss of love. She doesn't get that he stays with her, sleeps in the same bed and can't even hold her. She doesn't get that he flinches when she tries to touch him. She doesn't get that he doesn't want comfort from her. She doesn't get that she's nothing, now, when, eight weeks ago, it seemed like she was everything. Someone whose eyes he avoids. Someone who barely exists for him.

She doesn't get any of that; and suddenly it makes her want a little recrimination.

"You cheated on me?" she whispers.

His shoulders rise and fall in a shrug that adds just enough extra hurt to make tears form in her eyes. "We had something in common," he says. "We both failed my daughter and my . . ." He swallows. "Her baby. You can call it cheating if you want. I'd call it fucking away a sense of mutual deficiency." He snorts a ragged laugh through his nose. "If it makes you feel any better, it didn't work."

Her patience hasn't quite snapped yet; her heart hasn't quite broken. But now she's folded next to a metal shelf full of syringes and catheters in one of the less used supply closets. Crying until her eyes hurt and her chest aches.

With each gulped out sob, she comes a little closer to giving up on him.

"You all right, Grey?"

"Yes, Dr. Bailey," Lexie says, ashamed of the smallness of her voice. She lowers her eyes, knowing they're still puffy and red despite all the washing she did in the restroom.

Bailey squints over her surgical mask, digging into the open abdominal cavity beneath her hand almost without needing to look. "How's Dr. Sloan doing?"

It seems like a new question, but her tone leaves no doubt that she's not really asking about Mark, just employing a different tactic to get past the dutiful, rote answer.

"He's," Lexie swallows, "as well as can be expected." Honestly, she expected something different (she expected him to want her to be there for him; she expected love mixed in with the sadness) but it's what people say and, increasingly, as much as she hates it, communication has degraded to well-worn expressions. (It's safer that way.)

Bailey nods. "Fifteen blade," she says to the nurse, falling silent as she makes a small, careful incision, then hands back the little scalpel. "Ten," she says, holding out her hand, and begins to cut again. When she finds her rhythm, she says, on a continuum with her requests for surgical implements, "He lost his family, Grey. That must be very hard on him."

"Yes. It is."

"And on you."

A pause passes between them, until Lexie breaks it by shaking her head rapidly. "No . . . no, it's . . ." (Awful. Freaking awful. Every screwed up moment of it.) The trailing off is horribly expressive, but Lexie finds herself incapable of denial. The most she can manage is not blurting out the words in her head.

"Clamp." Bailey clears her throat, depositing the scalpel in the metal dish held out by the nurse. She eyes Lexie. "Would you like to close, Dr. Grey?"

"Me?" Lexie squeaks. Between guilt and rejection, she's almost forgotten what it feels like to be offered a privilege.

"You see anyone else named Grey in this OR?"

"No," Lexie says warmly. She's so grateful for the sarcasm, the normality of attending-resident interaction, she could almost kiss Dr. Bailey. "Just me."

"So close," Bailey shrugs, impatiently beckoning Lexie around to her side of the operating table.

There's a blissful twenty minutes of stitching, quiet instructions and no thought about anything else.

Then, scrubbing out, Dr. Bailey leans towards her a little. "And on you," she repeats. "You need to take care of yourself, Grey."

Lexie suspects she means warm tubs, massages and early nights with a book that's not about surgery.

She has other ideas.

After some not so subtle questioning of nurses, she tracks down Alex in an on-call room. He's sitting on the bottom bunk, bouncing a small rubber ball hard against the opposite wall as though he'd like to kill someone.

"Hey," she says, moving as close to him as she dares.

"Get out, Grey," he says wearily.

"No." She swallows. "I need you for . . . something. I need you," she takes a deep breath, "to have sex with me."

The pounding stops as he abruptly catches the ball and holds it in his hand. He turns his head and raises an eyebrow. "No."

It doesn't hurt as much as when Mark said it but, somehow it makes her madder. "Out of loyalty to Izzie?" she demands. A part of her wants to sink into the floor right about now, but the stubborn part stands its ground, feet planted to the floor, hands balled in fists at her side. "Because, you know, she's probably cheating on you right now with some guy she used to date and said she'd forgotten about." (It's her life, not his but, for all she knows, it fits him too. And she figures, from the little she knows about him, angry sex might be his thing.)

"Lexie –-" he begins, but she's on a roll now.

"You have a non-marriage and I have a non-boyfriend. We're in the same freaking boat, except Izzie had the decency to actually leave. Why shouldn't we have sex?"

He pulls a face that's somewhere between perplexed, pissed off, amused and half-considering her offer. "'Cause I don't want to," he finally says. Then adds, "No offense." He pauses. "It's just I've been there, done it –"

"And I was forgettable?" she blurts out. "Well, let me tell you, Alex Karev, I've learned a thing or two since then!" (From Mark. The thought makes her throat catch, but she plows on.) "You'd be lucky to have sex with me!"

"Not you, dumbass. Cheating on Izzie." He rolls his eyes, then shrugs again. "There are limits, yeah. And when the time comes . . ." he shakes his head, "let's just say there are limits." He pauses. "But you need to work it out with him, not me. It's gonna take him a while. He lost his family."

"Did the Chief get you all together and give you little cards with what to say to the inconsolable manwhore's pathetic girlfriend?" It was supposed to be clever and cutting, but her face is burning and tears are suddenly rolling down her cheeks and now she's just standing there helplessly crying.

"C'mon, Grey," he says awkwardly. "Don't, Lexie, okay? Seriously . . . no offense." He gets up, closes the space between them and brushes a thumb gently across her cheek to staunch the tears. "You weren't all that forgettable," he says quietly. "I just had other stuff on my mind."

She presses a hand against his chest and reaches up to kiss him, assuming from the intimacy of his gesture and the soft hoarseness of his voice that he's changed his mind.

"No," he says gently, pulling back from her. "Work your shit out with Sloan."

He's right, of course, but she's a little out of control now and past being able to take it all in.

"I just wanted sex." She doesn't know now if the tears are heartbreak or anger and frustration. "I didn't want your bad boy turned Dalai Lama Yoda act!"

She slams out of the on-call room and spends the rest of her shift scribbling her way illegibly, pen pressed too hard, through a backlog of charts and resolves, on the way home, to buy a massive bottle of tequila. She is not Meredith's sister for nothing. Where boys and sex are not forthcoming, there's always alcohol.

(She ignores with all the willpower she has the wrenching feeling inside when she thinks about home.)

The apartment is dark but, when she turns on the light, his leather jacket lies discarded on the floor, his bag a few feet away and the bedroom door is closed.

She assumes he's sleeping.

Clasping her tequila bottle in a brown paper bag, she fetches a tumbler from the kitchen, a plate and a knife for the limes she bought in an attempt to make it seem less squalid, and spreads it all out on the coffee table next to the couch.

Perhaps Joe's would have been less wretched, but (as Meredith would say) she's drinking. And the apartment is more convenient for throwing up and passing out and not having to listen to anyone tell her that Mark is complicated, or to give him time because he lost his family.

(He didn't even like Sloan, she bitches inside her head, ignoring her shame at the small-mindedness she's begun to embrace, as she pours her first, very large glass of tequila.)

Her eyes flicker open, dazed from the sleep she fell into, empty glass awkwardly half-grasped in her hand and resting against her knee.

Mark is sitting at the other end of the couch, leaning forward with his head in his hands.

She clears her throat softly and, when he looks up, she sees his eyes are red. In all this mess, he has never once cried (to her knowledge, anyway). And drinking and falling asleep apparently left the skin of her heart a little thinner (the opposite of her intentions) and she feels a little pain on his behalf.

He gestures towards the tequila bottle. "Can I get some of that?"

She hands over the glass and watches as he pours a small measure and drinks it down, not bothering with limes.

"I hate this stuff," he says hoarsely, pulling a face.

"You always say that," she says, forgetting for a split second that they're not them anymore.

"Yeah." He puts the glass back down on the coffee table and pushes it back in her direction. "I was thinking. This is . . . " He sighs. "You're not happy."

"I—" No would suffice – it would be a plain statement of simple fact. Instead, she hunches up further towards her end of the couch, defending her territory, and says, "I almost slept with Alex Karev today." She's not sure if it's a confession or just spite. Once it's out of her mouth, she flinches, on his behalf perhaps, or maybe anticipating (hoping for?) anger.

He just nods.

"That doesn't bother you?" Lexie can't help asking. "It seriously doesn't bother you that I almost had . . . that I cornered Alex Karev in an on-call room this afternoon and almost had sex with him because you, you . . . God!" She inhales in frustration and huffs the exhale out through her nose. "Well, why would it? It doesn't bother you that you screwed Addison Montgomery. It doesn't bother you that you won't touch me, or talk to me or let me help you. It doesn't bother you that I'm suffocating here. And yes, I get it. You're complicated. And I should give you time. And you lost your family. I get it. But we were . . . we were something. We were something good, weren't we?" He doesn't respond. "And I was there for you. And for all those reasons . . . for all those reasons I decided not to be hurt by you and Addison; I made myself not be hurt. And now you won't even look at me; and I'm humiliating myself in on-call rooms and drinking tequila by myself."

He swallows. "I was thinking," he glances sideways at her, "maybe we should break up."

She knew this was coming. She even wanted it at some level and everything she said just now was more or less forcing the issue. But that doesn't make it hurt less; doesn't mitigate the sharp breath that slices through her chest; and when she stands up, it's accomplished by willpower, pain, tequila and a truth composed of insulating lies that aren't even working. "I think maybe you're right," she says, before walking into the bedroom and slamming the door.

The door opens a fraction. "Lexie."

She doesn't look up, extending the pretense that she's actually reading the book she's holding to Mark rather than just herself.

"Lexie. Can I . . . ?"

She shrugs. It's the only answer she has. He comes in, closes the door softly behind him and sits down in the chair by the window.

"I didn't mean to hurt you," he says. "Addison and me . . . . it was . . . " He hunches forward and massages his temples. "Shit, I don't know, it was -"

"Fucking away mutual deficiency?"

He licks his lips and half nods, then shakes his head. "That was . . . I was out of line. I just . . . I'm sorry I cheated on you." He glances at her, eyes lingering for a second on hers, before dropping again, avoiding, as he runs his hands slowly over his face. He inhales, as though he's getting ready to speak and Lexie finds herself holding her breath, waiting and then exhaling with him. He glances at her again, his eyes trying to tell her something. But it passes, the communication dies again and all he says in the end is, "I just think it would be a good idea if we broke up."

"You don't love me anymore?" she asks, challenging, not knowing which answer she wants more, yes or no, just knowing she wants something real.

"Do you love me?" he asks. The question is unfair, but (mostly) rhetorical, his worn out, skeptical tone implying the answer no.

But it's not that easy. She has not loved him recently. She has told herself that, at least and it felt true. But she cries and her heart almost breaks and she stalks Alex Karev for sex he doesn't want and drinks tequila on her own. And still, if Mark wanted her, she would be there for him. So she thinks, as much as she can from a place where nothing makes sense anymore, that no is the wrong answer.

"Yes," she says, and any part of her that still doubted the truth is silenced when he swallows and nods and she can't bring herself to ask Do you love me? out loud again, because in a few short moments, she knows the only response she can deal with is a yes in return.

"I can't," he says finally, answering the unspoken, unsteady question. "I can't love you." He tips his head back, letting it meet the wall behind his chair. "I can't feel anything."

"Well, you need time . . ." she hears herself say and almost adds a sorry for the cliché, but Mark speaks first.

"That why you're replacing me with Karev?"

A little anger rises in her throat (and a little hope at the trace of resentment in his voice). "I wasn't replacing you," she says tightly. "And, frankly, when I told you, you didn't seem to care." (It's self-protection. She's ashamed and defensive, and she cares enough for both of them.)

"I told you," he says gruffly. "I can't feel anything."

"Then why ask me if I love you?" She hates the twists and turns of this conversation, of her moods. They used to work; they used to be simple (in all the ways that mattered); now they're complicated.

He swallows. "I can't feel anything. That doesn't mean I don't." He looks at her then, eyes darkened with sadness, not avoiding any longer.

"He didn't want me," she offers, unequal to his eyes. "He told me to go home and work things out with you."

Something that might be a smile if it wasn't so defeated crosses his face. "He's an idiot," he says softly (the reminiscence makes her gasp inside). "On both counts." He pauses, then says thickly, "I cried. In L.A. For Sloan, for the baby . . . for myself, I guess. I cried when I fucked Addison. I fucking cried when I came." He shakes his head. "She was just a kid. And the baby . . . my," he laughs softly, "my grandson. He was . . . a possibility, you know? A possibility that everyone with my genes isn't a lost cause."

"You're not a –" she tries to comfort, instinctively, without even thinking. But he breaks in, not listening.

"I thought it hurt when Addison had an abortion. I thought that hurt. But this . . . this is." He scrubs a hand across his eyes, but when he looks at her again, the tears he was trying to hide are still there. "I failed her. I failed her in every possible way. Addison was right. I'm a fucking terrible father." He pauses. "So I can't feel anything. I can't love you. I can't care about you and Karev or the fact that you're starting to hate my guts. Because if I feel that, I have to feel the rest of it and I don't know how to do that without going insane."

He stops then, lowering his head again, underlining his words with the physical gesture. But just before, there's a glance, something on the point of disappearing, something hopeful, something that asks her to understand, even though he doesn't and, like he said, can't and, in that moment, her heart's in her mouth. "You still love me," she whispers, almost entirely to herself, because she knows he can't answer if she poses it as a question.

She waits for him to deny it, but he doesn't, just breathes in and out. And when she quietly takes his hand, he doesn't pull away.