My friend says hurtful things for no reason?

Your friend does seem to have a few problems in her life, and this outburst may have not really been aimed at you. See if you can get her to talk to you about problems at home etc and sow her that you are her friend and not out to hurt her. So yeah it might not be her being "Bit*c*y" Just her taking it out on someone she thinks wont leave her.