in my experience it is...when i was young used to hav the occasional nightmare and get scared...then i naturally started gainin awareness in dreams...and now many dreams that wud hav been a nightmare in the past are just another normal dream with a horror aspect to it.

Lucidity is a great way to combat the fear...if you can appreciate that no real harm could come to you and that the dream isnt real then it allows you to go forward in the dream without the fear.
I cant control my dreams totally however i can end them whenever i want and i think that is another lucid aspect. If i get too scared i can just end it...sometimes iv found an escape from the dream...i want to leave so i find the vehicle or safe place tat allows me to escape etc.. so yes lucidity is def possible in nightmares and it can help control ur fear.

Hope this helps