Close in 7 days tenant won't pay rent.

[Ramon Moreno]

Hello BP family, can any one tell me what to do? I'm selling my building and I'm set to close in 7 days,  my tenant just told me that she's not going to pay rent this month (month to month lease)and to use her security  deposit because  she plans on moving. Are  there any legal issues I should be worried  about? She made it clear that her sister  was a lawyer  and that she  knew her rights. she also said I was being misleading and dishonest. The the thing is I never told her she had to move. In fact the new owner said he wanted her to stay........ am I screwed?