AN: Bringing this here from ao3. It is still very much a work in progress that is ever-evolving as new spoilers come out.

It started out as a trickle. A little river of affection, flowing gently. It also started quite by mistake. Looking back on it now, she wonders how she didn't recognize it for what it was.

Back then, they were full of self-righteous anger and frustration, brimming with fear, both too similar to realise they shared the same fears, had the same self-loathing belief that they were not enough.

If she has to pinpoint it, she'd say it was trickle at first sight. Standing there on the dark pathway to the big house, watching as the immaculately dressed brunette flung her arms around the little boy. It was almost bittersweet, in a way. To know that the kid, her son, had found a mother who would hug him so openly, one who was so obviously worried about him, that wanted him around… she was glad. It's all she wanted when she'd given him up.

And yet at the same time, there was a stab of longing, deep in her gut. Because Graham stood behind her shoulder, and checked on the kid, and god, she was beautiful. Too bad she'd never have that, would never have someone to worry over her if she didn't come home, wouldn't have someone to share responsibilities, such as checking on children, with.

Of course, it had turned out the thing with Graham wasn't quite what she'd first thought, but the longing lingered. It lingered through the fights, and the screaming, the crying and the constant bickering. It lingered through the quiet moments of companionship, the few times during that first year where it seemed that maybe they could have a truce – the moment by the mines, when she could have sworn Regina nearly kissed her, subdued moments by a prison cell with her parents.

Through all that, the desire to belong, to be needed, to be loved, had lingered. Even after the curse broke, and she had more family than she knew what to do with, and all crammed into the loft, something was missing, and she still couldn't shake the longing. She wasn't even sure she wanted to, by that point. It had become a companion of hers at all times, and it came with daydreams and the idea that it might, maybe, possibly, one day happen, so she didn't mind it so much, really.

It was standing by a well in the forest, her son tucked under her chin and his other mother leaning against a tree, smiling at her, that she felt the longing disappear for the first time.

It came back minutes later, when they'd all parted ways and gone to Gold's shop, but she couldn't forget how the longing had shifted to a sense of belonging, even for just a second. So she tried to see if it could happen again.

And it did, more and more as the months went by. First with a quiet smile – both inside and outside of Granny's, that night before it all went to hell again – and then more pronounced ones. It changed with disbelieving looks over a trigger, and being stronger together; it changed with doing magic together. It changed to something else altogether, an amplified version of the longing (but no, of course, it wasn't grief, how could she grieve something she'd never actually had?) at the town line, with the Bug and Henry on one side, everyone else on the other.

The belonging came back a year later, after New York, sitting in the office, trying to make the impossible situation somehow better, not able to comprehend the pain Regina must be going through, to have Henry not know her. But the belonging came back that day with a vengeance. It came back with soft smiles and trusting looks; it stayed with worry, with working together, with magic lessons again. It grew with a second curse breaking, and a helping hand in protecting her family.

And then it went crumbling away again with guilt.

Guilt didn't stay very long, at least, not in the way she expected it to. It was swirling around, faster and faster, with the longing and the anger and the fear and the jealousy, all swirling together into a never-ending vortex in her head; until the day belonging came back, timidly, with magic again, and all the others, that maelstrom of feelings and emotions, got pushed back, left to swirl away in the darkness. Not forgotten, but ignored. For now.

And as belonging grew, took shape, it pushed the maelstrom further and further away. Jealousy left completely for months, and the swirling stopped being so violent. The guilt ebbed, too, allowing the anger to calm down.

So she was left with belonging again. It reared up with kale salads and late night confessions; with trust that went both ways, and an inability to stop saving each other (and really, they should have life insurance, because Storybrooke never stayed quiet for very long, and the big bads were always after one of them, which inevitably meant they were after both of them, since they were both pig-headed and stubborn, and that fear always showed up again, the fear that the belonging would once again lose the be, leaving just the longing…); with best friends, silent communication and a helping hand to reach the happy ending.

Even if that happy ending made the maelstrom start up again, first quietly, then slowly growing in strength.

But the belonging didn't leave this time, it just joined the maelstrom. It swirled around with the jealousy and the fear, and that made it worth it all. Made the road trip to find the cheating scum worth it, because Regina needed her, and it was the first time anyone had said that to her, and it was Regina that said it, so how could she not go?

The belonging even stuck around in that new world of the Author's, when up was down and her mother wanted to kill her. Regina still trusted her, still believed in her, still wanted her to be happy.

And it stayed when they got back, too. Stayed through the party and the jealousy, burning hot because how could she be with him, when he'd married her sister not twelve hours before, the same sister he'd gotten pregnant?

But she'd found that belonging had made roots in her heart – and in Regina's too, she supposed, since belonging depended so much on her to exist – and refused to leave. It was there when she reached towards Regina helplessly, as the darkness came for her. It was there when she knew what had to be done. It was there when she ran, unthinking, towards the darkness, not caring about anything or anyone but the belonging that came from Regina.

And it was there when the darkness took her, instead.

Even now, when all there is is darkness, and she's not even sure whether she's dead or alive, the belonging it still there. So she tugs on it, testing, wanting to see if maybe it'll bring light again.

It started with a trickle. But by the time she got lost in the darkness, it had turned into a gushing river, with currents and undercurrents, pulling her headlong, pulling her home.