Friend problems?

Ok so i've known this girl since 1st grade and we've always been friends, but she gets so annoying sometimes. In 5th grade we went to diffrent schools and stuff but we still kept in touch and it was easy becuase we werent in the same school so she wasnt as annoying to me, but lately she calls/texts Ims me all the time and is so annoying to people that she has no friends but me and i'm not even her friend anymore in my opinion! And then today i get a text from her saying shes gonna transfers highschools and come to mine! I dont want her to come and so inmature and annoying and i've tried to be nice but i cant anymore! All my friends know of her and dislike her as do I. Should i tell her not to transfer schools? or should i wait and then ignore her when she comes. This is so hard for me becuase i hate being mean and everyone tells me im like one of the nicest people they've ever met but i just cant deal with her anymore I need advice.