In the end, it's Bucky who convinces him.
"You should do it, Stevie," he says. "You owe it to yourself. How many years are you gonna keep putting everybody else ahead of you?"
"As many as it takes, Buck," Steve answers in exactly the way Bucky knew he would. "Half the Earth's population just came back from the dead. They're going to need help acclimating to the world as it is now."
They're on the back porch of Stark's and Potts' house, staring out at the lake in the moonlight. The memorial service is tomorrow morning. Bucky has never felt like he belonged anywhere less in his entire life. It's not just the casual, homey opulence that still makes a tiny, cold part of him feel like he's there to kill someone (he's not. He knows he's not. He doesn't do that anymore; never will again. He just has the intrusive thoughts sometimes). It's how the first time he met Tony Stark he tried to kill him, and the last time Tony tried to kill Bucky instead. Steve said he and Stark reconciled, but he didn't tell Bucky he'd been forgiven.
Ms. Potts has been nothing but kind and gracious, even through her grief. But it's still hard to be in the home of a man who hated him.
He's here for Steve, though. Just like tomorrow he'll be there for Steve, even more than to honor the man who gave his life to save everyone.
He'll always be there for Steve, even if that includes telling Steve to go.
"There're plenty of people to help with that," he says. "It doesn't have to be you."
Steve looks at him, then. In the moonlight his eyes are bright with pain. "We lost Natasha and Tony. Thor's leaving, so is Clint. Bruce may never be able to fight again. I can't just abandon the Avengers who are left!"
"But Clint and Thor can?" Bucky crosses his arms, faces Steve with his eyebrows raised. "They're fucking off to have lives of their own, why can't you?"
Steve opens his mouth, closes it. He puts his hands on his hips, turning away. "Tony and Natasha laid down their lives for the world. How can I do any less?"
He's said that before, standing outside yet another recruitment center, glaring up at Bucky with all the righteous fury his tiny, sickly body could contain. Bucky remembers it exactly, just like he remembers what he said next. He doesn't quite say it now. "You got nothing to prove anymore, Steve. You've done your time. Given more than anyone had any right to expect. You've been fighting for other people your whole life. It's time to fight for yourself, now. You've earned it." He steps closer, putting his hand on Steve's arm. "You deserve it. You deserve to be happy."
Steve swallows, but he lifts his head. He gives Bucky one of his uncertain smiles and just like always, Bucky is hit like a gut punch with just how beautiful this man is. How fundamentally decent. How much Bucky loves him.
"Everyone deserves to be happy," Steve says.
"Exactly." Bucky rubs Steve's arm, and makes himself smile, forcing all the warmth into it he can. "So, be happy. Go get your best girl and be happy."
Steve's smile disappears. "What about you?"
It's easy enough to keep smiling, add an innocent blink. Bucky doesn't tend to like pretense much anymore, but he remembers how to do it. "What about me?"
"You deserve to be happy too," Steve says, eyes big and earnest. "And if I'm with her…I can't be with you." He puts his big hands on either side of Bucky's neck, his thumbs caressing the line of Bucky's jaw. "I want to be with you," he says quietly. "I want to be with both of you."
"Yeah, well." Bucky keeps smiling. "I'll be right here when you get back."
"I know, but…." Steve takes a breath. There are tears in his eyes now. "God, I'm gonna miss you."
"I'll be right here," Bucky says again. He wraps his hands around Steve's, holding them between their bodies. "Anytime you want."
Steve shakes his head wordlessly, eyes streaming. "I can't," he rasps. "I can't. I can't leave you." He sniffs, manages a fleeting, fragile smile. "Come with me?"
Bucky has always been good at laughing when his heart is breaking. Now there are tears in his own eyes too. "You know I can't do that, Stevie. They wouldn't let me, for starters. And one of us should stay young and pretty for Sam. He'll get all mopey otherwise. Nobody wants that."
Steve doesn't smile. "I wanted to give the shield to you."
Bucky shrugs but he keeps smiling. He lets go of Steve's hand to clear some of the water from his cheek. "I'm not ready," he says simply. Right now he's not sure he'll ever be. "Sam is. And, he's a hero, Steve. I'm the Winter Soldier. I got too much red in my ledger to be Captain America."
"You've always been a hero, Buck," Steve says. "What Hydra forced you to do doesn't change that. You deserve that shield as much as Sam."
That's debatable, but Bucky knows better than to argue; Steve's already sad enough. "He'll be a great Captain America, Steve," Bucky says instead. "He's the right choice. And what you're doin' tomorrow is too."
"I didn't say I was going to yet."
"You will," Bucky counters. He takes Steve's face in his hands and kisses him, trying to fill it with every iota of love he can, enough to last Steve the next 77 years. Their lips taste like salt. "You will," he repeats when they break apart. "Because you deserve it, and so does Peggy. And 'cause I'll be right here when you get back."
Steve swallows again. He cups Bucky's cheek. "'Til the end of the line, right?"
Bucky nods. "Always," he rasps. His throat is too tight to let him say anything else.
Then he pulls Steve into a hug, holding him like it's the last time.
It always feels like the last time.
"Thank you, Bucky," Steve says. His voice is shaking. "I love you."
"I love you too, Stevie," Bucky says. "More 'n anything."
Enough to let him go.