Does She seriously have a case? Visitor, Guest

A female friend came to me and told me that she was homeless. She asked me if her and her 21 year old daughter could stay a few nights. (not to mention 2 dogs) They were here about 2 months.
They are NOT on the lease.
They have no mail in their name coming here.
I was paid no rent (it was discussed, nothing was ever written down nor monies paid)
There was never any discussion over whom was going to pay for what amount of food etc. She finally found a job and started working, but her daughter just vegged out watching tv. (and ate most her food that she is now going to sue me for-.-)
I gave her week's notice to leave. She got angry and yesterday dropped off a handwritten note to me telling me that she was going to tell the landlord (whom she has rented from before although I don't know how well their relationship is) that I sub-letted my apart to her (to get me kicked out) and that I owe HER for the food that she bought that I, my husband, and my child ate, for the time that she spent doing normal cleaning chores, a load of laundry, and for the time she spent with my child. (i never left the house and he is 6) She also included in her letter that she was going to do all this if I did not pay her or talk to her by 10am this morning, and that I would be liable for her court costs as well. (I never went, I don't want to even see her at this point since I am so livid.)

I already plan on talking to the landlord myself and tried calling him this morning but got the voice service. Also, isn't this extortion, or at the very least harassment?
Does she have a viable case?