
Aside for going back to the forest in order to prevent another dimensional war, she doesn’t actually have a reason to run away. Not only is she not scared of him, she also has a soft spot for him. Her only plan now is to wait it out until the forest heals. Then she’ll leave, but only to prevent a war. Not to get away from him.

That is reasonable and could be true though half of the stories that are similar to this always have a chase arc which personally I'd find that pretty satisfying and look forward to seeing in this manhwa if possible. I also I don't think she'd(mc) would take being caged in a palace for a long time very well, but we'll see how it goes anyway.
Okay so when will she run away?