First, get a good lawyer.
Second, ask your Realtor what the status is.
Third, if your Realtor doesn't know, ask the seller what the status is.
Fourth, I'm unclear whether this was an actual short sale, or whether the seller was expected to bring money to closing, and didn't. I'm not a lawyer, so this isn't legal advice. However, if it was a short sale and payments aren't being made, it's headed to foreclosure and soon the bank will own it. If it isn't a short sale and the seller's trying to round up the needed money, is the seller behind on payments? If so, it'll progress to a foreclosure and the bank eventually will own it. If the seller is current on payments, then you're a tenant in the property. (If so, do you have a lease? You should.)
You really have to determine what's happening to the ownership of the house while you're sitting in it. And, in any case, you need to resolve this as soon as possible.
So: Lawyer. Realtor. Seller.
Hope that helps.