Loki ends up in a secured room with SHEILD or something, they discover he's been mind controlled but he freaks out and panics a lot. I think there's a scene where he hides under the bed/or cowers at the other side of the room. I think maybe someone tried to kill him while he was in there? I believe he also made a few attempts on his own life, and Thor has to restrain him? I can't remember clearly, but its possible Tony and Thor were his main visitors. 99.99% sure it was on AO3.
I hope someone knows what I'm talking about, I really loved this fic and I'm sad I can't find it. :( Thanks in advance! Even if it's not this fic, anything with some similar concept would be amazing and please rec it to me if you know of any. Thanks again!