She may not have foreseen the rocket attack on the plane, but it was going down in Dogtown regardless due to her hack on the navigation system. The 'hack that she didn't have time to stop' was her hack and she was in cahoots with Hansen from the start. As for finding out about the one-time AI use, she knew about that since Cynosure (or whatever the fuck it was called). So long enough, but still kept lying to V so that 'she'd be sure you'd help her'. As for the stadium, regardless of how it plays out in the gameplay, she makes it quite clear that she's fine with having civilians massacred and when V voices an objection/abhorrence pointing out that a lot of people will die, she shrugs and says "they'll die so that we can live", but which she means so that
she can live of course. She has no regard for life, except for her own. She also betrays literally everybody in the game: Myers, Reed, Hansen, V. Reed didn't force her to join the NUSA either. She wasn't a "naive netrunner." She was already doing illegal shit and so ended up with a choice between netwatch or nusa and chose the latter. In addition, she got infected due to actions that she carried out (dabbling with the blackwall) by her own volition. Nothing with CDPR is ever entirely black and white when it comes to major choices, so I understand that your viewpoint is different. Personally though, I just felt that she was a narcissistic sociopath.
In terms of the heartbreaking bit, yeah, the ending that you described admittedly sounds awful. I've never called Reed to accept the surgery though.