Can anyone help me because I'm getting different answers, i had a friend who I fell out with and she blocked me on Facebook, we have sorted our differences and I want to add her again as a friend, unfortunately the friend request is greyed out and I am unable to add her again ?

Means she has disabled friend requests .... send her a message maybe

Tell her you'd like to be friends again but she needs to unblock you first.

Either that or set up a new account where you'll be able to see her again.