I have a friend that....?? help!?

whenever my friend comes over she always walks around naked?? like completely?? and sometimes she pees herself and leaves used tampons laying around and clogs up the toilet with them. sometimes she seems normal and nice, but then she just goes completely insane later. like in public she will point at people and scream LOOK AT THAT FAT PERSON!!! or OMG WHAT'S WRONG WITH HIS FACE?? and it's reallllly embarring. in movies she always laughs extremely loud and writhes around in her seat and tries to snuggle up with random people. she likes to compare sizes with people too and occasionally grabs her and groans. it's really disturbing what do i do