My mates moved in.

I let one of my best friends move in with me,
because her parents kicked her out.
Unfortunatly we are sharing a room and she is already having a sook over my bf coming over even though he doesn't stay long.
but she thinks she can have hers over whenever she wants.
she has only been here for 2 days and i don't want to say anything to start a fight already.
PLEASE HELP!!

I can't ask her to leave.
my mum thinks of her like a daughter i've known her that long.
and her parents don't even want to speak to her.
and she won't tell me why.
thanks for the advice.
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