This is pretty much the direction I was hoping it would take. In a way, she's kind of a reverse Odin, who gained great insight when his eye was devoured. For B-Ko, it wasn't so much self-knowledge she gained, but knowledge of A-Ko, which gave her the strength needed to actively pursue a relationship she'd passively went along with up until then.
Of course the symmetry at the end capped things off nicely.