3. The mission
Of course, some days are worse than others. Some days Steve knocks on the door and no one answers. So he waits, and waits, but he knows Bucky's here cause the building manager smiled at him when he arrived - when Bucky's not here, there's no smile to be seen and he simply shakes his head.
It's happened a lot. When Steve has some free time between two missions, he does his best to fly off to Romania and visit Bucky. It's been almost a year that Steve found out about the apartment now. But of course Bucky's not always here. He has to be on the move if he doesn't want to be discovered. It's probably not his only apartment, he's gotta move from country to country. Romania seems to be his favorite though.
Still, Steve has no way to check that Bucky will be here or not when he arrives, he has no way to contact him. So he just goes, cause if there's a chance he'll take it, but yeah, sometimes he arrives and the building manager shakes his head and Steve leaves.
And sometimes Bucky's here, and he doesn't always remember him. Sometimes he remembers a lot, sometimes all he knows is that Steve's a friendly figure. But Steve talks to him and things get a little - sometimes more than a little - better. One step at a time.
Natasha knows, it's too obvious to keep it away from her now. She doesn't say anything. Sam will probably find out soon as well. And Steve blames himself for not telling him, but there's not really any point in telling him in the end.
So Steve is standing in front of the door and no one answers and Bucky's inside. He probably doesn't remember anything. It's happened before. Sometimes Bucky doesn't remember, but Steve comes in and talks his way through him and it gets better.
Sometimes Bucky doesn't remember, but Steve is reckless and he doesn't care cause it's his best friend and he's not gonna let him deal with it alone, not anymore. Like today. So Steve carefully pushes to door open - Bucky never locks that poor, thin wooden door, what's the point when the people that are after you would be able to breach a bunker? - and takes a few careful steps inside.
And then there's a hand on his throat, strong and cold, and those furious blue eyes that look greyish now, filled with rage and uncertainty. Steve doesn't say anything and he's staring at Bucky with all the gentleness he can put in one look, but the hand is squeezing and squeezing and he can't breath and « Buck, come on... » is all his strangled voice is able to let out.
He doesn't want to hurt him but he's too far gone right now and Steve knows there's nothing he can do to make it stop. So he takes hold of Bucky's metal arm and uses his knee to kick him in the ribs and sweep him off his feet, and then Bucky's on the floor, bloodshot eyes shooting at Steve and the metal fingers are already clenched in a fist again and crashing against Steve's cheekbone.
For a few minutes it's only Bucky thrashing and kicking and angry « Get out of here, leave me alone! » and « I don't care about the mission anymore, just go away! », so Steve knows it's the Winter Soldier talking to him - but not quite the machine-like Winter Soldier he met for the first time in D.C. either.
When he's too tired to keep parrying Bucky's furious assaults, it only takes him a couple of seconds to escape his hold and run outside the apartment, down the stairs and away from Bucky. He doesn't want to hurt him and that's the only way he can think of to keep them both safe.
He hates himself for leaving. For leaving him here, confused and broken, for not being able to help him. But there's nothing he can do to make sure his friend keeps his memories for himself. He can just be there and help him when Bucky wants to be helped, and back off when he wants to clear his mind.
(When Steve comes back to the US and to the Avengers HQ with bloody cheek and bruised forearms, and that desperate look in his eyes, somehow, everyone knows. No one says anything about it.)