My friend makes plans but never follows through. What do I do?

She makes plans to spend the night, go taning, go to the mall, etc.. Constantly! But never ever folows through. Some times she won't even answer the phone when I call. And sometimes she takes the phone off the hook. And everytime I try to make plans and she dosen't follow through I end up felling dissapointed and mad. What should I do teach her a lesson, avoid making plans, cut her loose. What??