I'm Lucy, and I'd be happy to answer your questions today. I'm sorry to hear about your situation.
First, you have no legal right to ask her to leave in one week. Legally, she's considered your tenant, and that means she gets one month's notice before she can be required to move out (or 30 days if you happen to be in New York City). N.Y. Real Prop. Law § 232-b. I mention this because, if you throw her out in a week and then sue her for the money she owes you, she can countersue for an unlawful eviction and you might have to let her back in, plus pay her damages. You don't want to be in that position. If she's stopped paying rent, then you can serve her a 3 day notice to pay or leave - just know that you have to go to court to file an eviction if she's still there once the notice expires. You have to be able to prove that you gave the notice, which means it should be in writing. Handing her the notice in front of a third party witness (or while making a video), is a good way to prove that you gave it to her.
For the money that you loaned her, that can be brought in the Town and Village Courts, which are designed to be fairly user-friendly so people do not need a lawyer. The courts have forms you can fill out to open a case, and you do not need a lawyer. You have the burden of proving that the money you gave her was a loan she promised to repay, and not a gift between people in a relationship. Text messages, emails, Facebook messages and similar types of communications can be extremely valuable for this purpose if she never signed a loan agreement. Or if you paid by a check that said "loan" (or even a Paypal transfer that said loan), that can also help your case.
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