On her good days, Peggy Carter knew she had Alzheimer's.
So when she first sees Steve Rogers again, exactly as she last saw him, she wonders how she can be having a good day and still be lost in the past.
She asks her nurse if she’d just had a visitor. The nurse replies that she did not, and Peggy is left to grieve again on her own, while the nurse leaves the room.
No one sees the nurse call her superiors at Hydra to report that Captain America had returned.
After each of Steve’s visits, when he talks about the old days and Peggy responds if she is able, the nurse confirms the visits to be only in Peggy’s mind. With new memories to build off of, some of the visits even are fake, but in her declining condition, Peggy can’t tell, except when Steve is small and skinny again.
The nurse is never far away when Rogers does visit; the entire reason she is positioned there is to prevent Peggy Carter from telling what she knows, but never wrote in any report.
Not any report that survived, anyway.
Because Peggy Carter knows Hydra survived in SHIELD. Her life’s work, tainted.
The nurse’s job is considerable harder, however, after she returns to Peggy’s room one night, and Peggy looks disturbed.
She asks what happened, and the retired agent mutters something about a man with a metal arm.
Alarmed, the nurse calms her and assures her it was just a bad dream. Then she calls Hydra again to find out that Hydra is coming out of the shadows.
The Winter Soldier had indeed been defrosted again, and had gone AWOL after being sent after Director Fury and then Captain America.
He is wiped, again, and the nurse prepares herself for her mission to be over.
Then Rogers visits again, and she can tell Peggy is struggling to tell him about the Soldier.
She recognized him, the nurse realizes.
When the Soldier visits again, the nurse walks in while he is still in the room. Instantly, there’s a metal arm wrapped around her neck, and she can’t breathe.
Then Peggy shouts.
“Bucky, no!”
And the Soldier stops. He stares at Peggy with wide eyes, and then he’s out the window like a ghost. This time, the nurse can’t explain away the bruises on her neck, and Peggy Carter looks angry, despite how feeble she is.
“You’re Hydra,” she says.
The nurse says nothing.
“I know what you did to Sergeant Barnes,” Peggy continues. “He’s remembering. He and Steve will stop you again.”
The next time Rogers sees Peggy, it is at her funeral.
The nurse watches from the back of the room.
She doesn’t notice the man with the jacket and dirty long hair watching from a much further distance.