She freaked out to get your sympathy. She knows the consequences but has been in denial & pushing her limits.

It might stop that reason for eviction but I am sure you can legally come up with some other cause to evict her on.

Unless you actually signed a lease agreement with her you can now say you have decided a lease agreement is required along with first & last months rent. What she will give you (if she does) is only back rent due & she would have to come up with the first & last which I'm sure she can't & that would be grounds tobget her out of there too.