Charges on my checkcard is this right?

I decided to go stateside while my husband is deployed so that our family could see our twins for the first time. My family stays in Athens, GA so my sister and I drove to Memphis, TN (this is where my husbands family is) while in Memphis someone stole my purse and her cell phone. I immediately called everything in as stolen (Pport, Dillard's Card, etc..) I didn't call in my drivers license or checkcard because I normally keep those in the diaper bag but today I realized my checkcard was in my purse and not the diaper bag so I called my bank immediately (Navy Federal Credit Union) and found out whoever stole it has spent all of my money in my checking account as well as sent my account into a negative. The lady I spoke with told me I still had to pay it back is this right? Are they supposed to hold me liable for being mugged? Up until now my account has always been in good standing I never overdraft!