How do I tell my friend I can't be her friend anymore??

OK so there is this girl and she is really nice but lately she has been really weird and awkward and clingy. Like she rubs my stomach and tells me I have small ears and I have a squishy stomach and stuff like that. What's her deal?? So anyway she has like 2 friends including me and she calls me her best friend ever. How do I tell her I need some space, or at least let her know I need to spend time with other friends at times?