All I took from it was that she had to take out an unknown number of assailants, by hand, to save everyone else. It took her to a dark place, where she had to become a killing machine, and it took away all of her laughter and happiness. Sort of like how "dying" (or whatever happened to him) took away a bit of Coulson's asshole-ness and made him care about people.
If there is more to it than that, I'll be surprised. I've got no idea where you guys come up with some of this stuff.
I got nothing about sexual assault, super powers, brainwashing, being able to teleport, etc. She just vanished from the dude on the plane because she's all badass like that, he was still just a normal rube when it came right down to it, he could just phase in and out of dimensions or whatever. Easy for her to trick and beat up once she realized what he was.