I already read this question but its more just rehashing the book: What does the Warlock's Fey Presence ability actually do? - my question has more to do with exact mechanics.
A mob of skeletons (undead) got the jump on me so I used Fey Presence to Frighten them since Sleep and Charm would have no affect.
I then ran away and all 5 skeletons took opportunity attacks against me. If they're frightened and won't move towards me shouldn't they be basically cowering for the moment allowing me to run away?