I've been there. Long long story short, I let someone I knew from college live with me cuz she was getting evicted (story she said was she lost her job and it was tied to her job since she worked at the complex, found out later it was for violence, drugs, and theft) she lived there for a year, owed me 5 grand I loaned her and caused 7 grand in damage. A bunch of other threats happened after her dog died (I took it to the emergency vet, put her on a ventilator, and everything, paid for it all cuz dog) and she was pissed I wouldn't take out a 30k loan in my name to pay for her dog. So after explaining she already owed me about 12k, she starts threatening to make up accusations to the cops about bunch of things I don't want to talk about (none of what she claimed ever happened and I got her on recording saying she knows it never happened)
Anyway, she starts talking about how she knows gang bangers, killers (her definition of killers was jiu-jitsu guys, weight lifters and mma fighters, who I know cuz I train with them) and that she was going to have me killed. She was gonna break in and strangle me, stab me, shoot me, poison me (all different threats) then it went to "I'm going to have someone kidnap you, slowly dismember you. And mail the pieces to your family. And then after I dismember your throat, I'll chop you up and scatter you on the desert so your family never finds you and can never have closure"
Cops did fuck all, so I had a gun on me at all times, even in my own house, I had my AR next to my bed, and anytime I went out I had my rattler in the car too.
She had (unbeknownst to me when I agreed to let her move in) she had been arrested multiple times for drugs, dui, assault, threats, and fraud. And with those drug charges, she definitely knew some people who would likely do it for drug money, so I took it serious.
Stayed like that for about 6 months before I finally bought a house and moved. Cops still ha went done anything even tho I gave them all the videos from my phone. My security cameras, voice recordings. Text messages, everything.
I even tried to get a restraining order, more so if something happened there was a paper trail and I had proof i tried to mitigate it, but it got denied.
Tldr; i had a psychopath roommate who never paid me any rent, utilities, or bought her own food (she'd judt steal my groceries) and threatened to kill me or have me killed when I wouldn't take out a 30k loan in my name for her, so I had to stay armed 24/7 for almost 6 months until I moved, because the cops wouldn't do anything