This is not as uncommon as one might think...and it actually within the OCD spectrum of anxiety. (skin picking is a similar manifestation)
Here is a link that gives more information, including treatment options.:)www.mentalhealthamerica.net/conditions/trichotillomania-hair-pulling
Getting the help you need, and working proactively to turn the behavior around will be worth the effort!
Best wishes, and keep us updated on your progress!