we have an old roommate who is claiming she has over 5000 of personal property missing from her items and is threatening to sue does she have a case?

April 12th she left the residence - she never "officially" (ie legally via driver liscense or changed mailing address to this residence) but she left - was in the house one other time to our knowledge and took items - after 6 weeks of no contact we had changed the locks and packed her items into boxes and placed them in the garage. She is claiming to have over 5000 of personal itmes missing and is threatening to take us to court. How would civil suits work? We have none of her items, and are unsure her motivation other than seeking cash. We HOWEVER have a 1200.00 bill from the insurance company when she was driving our truck and hit the neighbors car. I am wondering if a judge decides if she has a case... does she have to have receipts for these missing items (cause I caould say I''m missing all kids of things I never even owned....) and etc. This is a private residence. We had the police here when she picked up her items. We let her walk through the house escorted by an officer