Life, Sarah told her little boy, is a river of time that doesn’t stop. He would have to learn to swim, or he would drown.
From that first moment, in 1926 in the alley, he feels him in the edge of his mind, a presence, just a presence. He’s never heard anyone say anything about it in detail, just that when you meet your other half, you know it, you know it right away. Anything more explicit is taboo, considered too much knowledge for the general public, because not everyone has a soulmate.
His name is James Buchanan Barnes, but his friends call him Bucky, and his right cross, even at nine, is perfect. He could go on to be a lightweight, maybe even a middleweight boxer, but he won’t.
Bucky, for Steve, comes to mean a steady presence, hard and stubborn like himself, a rock he can put his back against and know it’ll be safe, that the currents won’t drag him away.
It’s 1939, and they’re standing on the narrow stairs outside Steve’s apartment, and Bucky leans in close, like he does. Squeezes Steve’s shoulder, right by his neck, and Steve can feel him, feel that steady, soothing presence, right in his head. It’s not that they’ve never touched, they have, of course they have, but Steve will only let himself have so much of Bucky, when he has nothing else. It’s sweet, like chocolate, sweet, like Coke, sweet like all the things that mess with Steve’s bloodsugar and make him ill, and Bucky knows that Steve’s afraid he’ll let himself get lost in Bucky’s warmth and strength and forget how to stand up by himself.
But Steve’s barely standing, anyway, so Bucky follows him inside. Five more minutes, his parents will wait. They’ve kissed before, but they don’t this time, they just stand there, behind the door, foreheads touching, and Bucky radiates all the feelings Steve desperately needs, and that Bucky desperately needs to give him.
The water keeps flowing, but even when the current pulls, he doesn’t feel like he’s going to drown. He has Bucky.
In 1941, they have equilibrium. They’ve gotten their own place, in DUMBO, because it’s cheap, that’s why. Bucky’s a journeyman auto mechanic, Steve’s teaching art in Harlem for the WPA. Everything’s quiet, everything’s cozy. They hum away at each other in the quiet times, spark at each other when Steve’s being stupid.
Bucky is a rock. Bucky is Steve’s rock, and Steve is Bucky’s. They brace against each other and hold out.
The war comes to Hawai’i, and Steve’s uneasy mind grinds away at Bucky’s steadying hum, until 1943, and the Stark Expo, and even when they’re close, they’re still grinding like ungreased gears. Bucky, Steve knows, in his mechanic’s heart, wants to take them apart, sand and slick them until they fit together again, and they’ll do that, he’s sure.
When the war’s over.
Except Bucky doesn’t make it that far, and without him, neither does Steve. Bucky fell off the train, and Steve kept going. There’s nothing to make him stop, and every minute of life feels like he’s approaching terminal velocity.
The plane goes down, and there’s nothing to hold on to.
It’s 2011. He surfaces, but there’s still nothing.
Steve tries to find something to brace himself against in the deluge of the future, but there’s nothing. He bangs against the currents, he finds a stream that isn’t really his.
It’s always a stream, never a haven. He can’t stop treading water. There’s nothing to rest against, no comfort. Even Peggy is slipping by.
It’s 2013, and it hurts.
Steve clutches his head and crouches to the ground, and the bullet nearly hits Fury when the director leans forward to check on him.
He grabs his shield and launches himself out of the building, chasing the assailant, but he’s not chasing the assailant, he’s chasing the pounding in his head, the stab of pain in a part of his mind that’s been silent since 1945. It hurts and hurts and hurts, and doesn’t stop hurting, and even when the wild gray-blue eyes stare at him over his own shield, Steve doesn’t want this, doesn’t want it, doesn’t.
Bucky isn’t supposed to hurt.
That Bucky was Steve’s soulmate wasn’t in their files, not even their SSR files. It wasn’t that Steve had lied, he had omitted to mention it, as Peggy had so sweetly put it when she had restrained herself from pouring tea down his pants, or shooting at him. Steve scooted over in her heart, and she made a space for Bucky.
Soulmates have always been complicated things.
Peggy never told, so nobody at Hydra knew that their asset was fundamentally compromised, that Captain America was the one mission the Winter Soldier could not complete. They didn’t know until after they’d been discovered, their most successful project destroyed, their asset lost.
"Don’t do anything stupid until I get back," Bucky muttered, turning from Steve’s body on the bank, leaving him there, stopped.
Steve’s washed up on the shore of the future. He found his rock, he found him hard, found it with his whole body at top speed.
Sam had a soulmate, too. He gets it. After Riley fell, Sam never stopped falling. They’ll wade out again, together.
Bucky isn’t supposed to hurt.
They lay in Steve’s bed in the middle of the day, foreheads touching, breathing in and out, and grinding like ungreased gears, sanding each other down, trying to put themselves back together.
They can’t hold out anymore, things are too deep. They’ll have to learn to float.