That one post which I can no longer find about how Laudna and Imogen simultaneously embody "I can fix her" and "I can make her worse" truly hit the nail on the head about them. They are each other’s tethers, keep each other grounded and help the other remember there’s a reason to go on, they taught each other that they don’t have to be lonely and isolated and feared, that they can be loved unconditionally not despite that which makes them dangerous and different but in part because of it, as an inherent part of themselves. They will fight for each other’s happiness tooth and nail.
But they are also the 'together either way' couple. Laudna would follow in Delilah's footsteps and burn the world and herself for Imogen. If she thinks Ruidus and Predathos are Imogen's destiny, what would make her whole and happy, she would encourage her to embrace it, Exandria be damned. Imogen exalted because of her love for Laudna. She was prepared to do just about anything to get Laudna back from the dead and is equally prepared to do anything now to stop it from happening again. She offered to let Laudna eat her soul. She's so so tempted by Ruidus and knows, even in her struggle, that the person she loves most would never hold it against her even a little bit if she gave in.