There's so many hard hitting quotes in this game. The one that hit me the hardest was actually the thought cabinet thought you get for trying to open the unopenable door.

Edit:

Found it.

"There is no way to open the supply depot door. Accept it. You cannot open all the doors. You have to integrate this into your character. Some doors will forever remain closed. Even if every single other door will open at one time or another, maybe to a key, or maybe to some sort of tool meant for opening doors... But this one will never accede to such commands. A realization crucial to personal growth. Crucial."

I felt so betrayed by this. I had spent a point to unlock this thought. I waited with excitement for its completion, which would surely allow me to unlock the door. But instead, I felt more called out than I have ever felt in my life.