She sounds like a sociopath. You can't 'win' against a sociopath unless you become one yourself.
I don't have any other advice. Cut her off, and cut off anyone else who carries her influence around with them in your life. Normal people struggle to understand just what these types are capable off, and often don't even realise themselves what is going on. Don't take it lightly.
I knew one girl like this who actually even admitted that this is what she enjoyed doing. She would average 2-3 guys per week, couldn't get up on time to work, was always broke but wearing the best clothes, and at some point tried to latch onto me on the pretext that I was a "good influence" to her. I won't go on. I didn't handle it brilliantly, but I handled it, and she moved away pretty soon after. She wasn't the worst I've come across, maybe half-way there. I figured out soon enough what I was dealing with, and confronted her on it, awkwardly. She called me a "creep", bolted, and now lives in a different town. It's quite hilarious actually, but the experience had me questioning myself a fair bit then.