When you make a plan god laughs. This is kind of the theme of the final installment. The final Battle of light vs dark was upon us. Alina, our reluctant hero, puts it all on the line to save Ravka. It’s only when she’s prepared to sacrifice everything that she gets her ultimate desires. The same can be said about the Darkling. On the surface he wanted world domination but underneath there was one thing he always wanted but never spoke of. And they gave that to each other.
In the end he wasn’t the enemy she thought he was. She realized life was more complex and the truth isn’t always simple. The end of their tales was perfect because the story wasn’t always pretty.