The Only One Who Knew Me/Merthur
In a world where your soulmate's name is revealed on your wrist, Arthur is too dumb to realize Merlin is the " Emrys " on his arm. Thus, Arthur hires a new, pretty, female manservant as to court her. Therefore, he begins distancing himself from Merlin (unintentionally of course).
Not only is it hurting Merlin, it is risking Arthur's life. Especially when branches stop falling on bandits heads and Arthur is the bandits' target.
NOTE: dang this is #11 in merlinxarthur rn as of may 19, 2018 so thank u guys!!