Roommate/tenant (29f) Threatening To Blackmail Me, House Owner, (31m) With False Sa Allegations

Location: California.

Roommate/tenant, has been living with me for 1.5 years, but there isn’t a formal landlord and tenant contract between us (foolish of me, I know). She just hands me a check at the start of every month for rent and her half of the utilities. We also began working for the same company in the same department about six months before she became my tenant.

I was looking for a tenant to assist with my mortgage payments and she was also looking for a new place to stay. So as cordial workplace acquaintances, I offered to let her rent from me and she agreed. Once again in hindsight, I probably made a huge mistake by not formalizing a landlord and tenant contract between us, but I trusted that both of us are adults and wouldn’t try to ratfuck each other. That is, I wouldn’t randomly evict her with no warning, and she wouldn’t trash my home.

This agreement worked out pretty well. This January, she announced that she would be moving in with her partner in August, so July would be her last month (I have this in text), which I acknowledged and had no problems with. I also missed having my home to all to myself so I didn’t mind her leaving, even if the loss of rent income would hurt.

Then she had a falling out with her partner last week and all of their plans to move in together have been put on indefinite hold.

She was waiting for me in the living room of my house on Friday afternoon when I returned from work, informed me of the fight with her partner, and told me she’ll be staying at my place for the foreseeable future. I insisted that she still had to be out by July, we argued, and she pulled her ultimatum, something along the lines of:

“You will let me stay or I will tell [our mutual boss and workplace colleagues] and the cops you raped me.”

Then she flashed the most shit-eating psychopathic grin and waited for my response. I gave her none, because I was so nauseated and terrified that I had to leave my own home. I’ve been living at a nearby motel since Friday night because I don’t want to give her any ammunition that she might use to fabricate allegations against me.

I’m at a loss on how I can defend myself against this. California is a one party consent state, so I know I likely can’t confront her about her about this and get her to admit she’s blackmailing me with BS allegations while secretly recording her.

I am no longer comfortable with this person living under my roof. But she’s made it clear that any attempt to evict her will result In her going public with the claims. I know I am innocent but I am terrified of the damage done to my social and professional reputation while the legal process (which I trust will ultimately exonerate me) unfolds.

What are my legal options besides calling her bluff and countersuing for defamation? How would I even begin to pursue the latter option, if I even should at all?

Thank y’all for your help.