My List has dropped one of my Buddies and I can't get her back I have tried everything that I can think of.

Welcome to the forums Ariana,

If you have refreshed / reloaded the game since this post and this particular buddy is still not showing up, and other buddies are, it is quite likely that the buddy has removed you from their own buddy list.

If you still feel sure, that it is a glitch with the buddy list, please use the help tab above the game screen to submit a ticket and the Vikings will look into it for you.