Us Against the World: A Captain America: Civil War AU Fanfiction

What if after the tunnel incident, Steve Rogers signed the Sokovia Accords? What if both Adelaide Lehnsherr and her lover, James 'Bucky' Barnes, were transported to a psychological center in America after he signed the Accords?
What would happen to them then?

2016. Berlin.

All Adelaide Lehnsherr ever wanted was to be happy. From the very first moment she stepped into the apartment of her boyfriend, James Barnes, also affectionately known as 'Bucky', in Bucharest, Romania, she could breathe again. The painful events of Ultron and Sokovia, as well as the burden of the years before, was behind her. The two were finally starting a life together, and she was nearly about to drop everything to move in with her boyfriend in Romania before that peace was shattered.
First Lagos happened.
Then the Accords.
Then the love of Steve's life, Peggy Carter, died.
And finally, the masked black cat-man came after them to kill them, claiming they killed his father in some freak bombing at the United Nations building in Vienna.
Adelaide and Bucky had no choice but to run, but they were soon caught and transferred to a CIA facility in Berlin.
Steve had no choice but to sign the Accords, but little did he know that Adelaide, his fellow Avenger, would not be given the same choice.

Stripped of her rights, and her powers, she and Bucky are seperated and thrust into the cold, clinical environment of an American psych center, where they must fight to declare their innocence to the world - that they were only victims of HYDRA, not willing killers.

Disclaimer: has mild smut and PTSD symptoms (BE WARNED, READ AT OWN RISK)