Unfortunately, it's the risk we run having an internet business. You may have been scammed, you may not have been. I'm beginning to find it worth it to make sure items have insurance on them. That way if a package is lost, the money comes from the insurance, not your pocket. I haven't had too many problems with this shop or the jewelry shop, but the USPS has lost too many of my soap packages lately. It's extremely frustrating.
You might also consider signature confirmation - my mom does this for her vintage jewelry, and it just saved her butt in a Ruby Lane transaction.