Thank you for sharing your thoughts, empathy and openness, that's a very healthy point of view.
OP, I just want to say that I completely and totally understand your feelings and frustration. The game stirred up emotions in you (in me as well, and in many others too). Then suddenly, it's like everything you believed, thought, and experienced in the game just collapses—and it feels like a slap in the face.
But! Don't let it take away your enjoyment of what is otherwise a brilliant game. I've started looking at it more as an exaggerated piece of fanservice meant to cater to a specific group. It seems the developers didn’t want to change anything—they thought it was fine the way it is. We just have to accept that, unfortunately, there’s nothing we can really do anymore.
One thing’s for sure, though: I’m convinced the developers never intended to humiliate Shadowheart’s character. I’d rather say her character was, in a way, sacrificed on the altar of fanservice, which is annoying, of course, but don’t let two or three optional lines ruin the character for you — they don’t define who she is!