Quoting Smartass *Preggo!*:" Yesterday I called the IRS to find out where my 3,000 tax return went and found out that I donated it to my husbands ex-wife. That was fun. lol"
Was it your return? Because you can file an injured spouse thing and get it back if so. My husband did it a few years ago when they tried to take our entire refund for student loans. It prevents them from punishing you for something the spouse owes. It's a PIA to do though because you have to refile completely with the new amended paperwork but you'll get most or all of it back in the end.
OP that SUCKS about the big bill.