That indeed really sucks Terry, very sorry to hear this story especially when it's one's main mode of transport. I know just has this feels as have had a few nice bikes stolen in my time.
I had a completely hand built Claude Butler Specialised Touring bike get stolen once.. in today's terms it would be maybe a £3,000 bike. I left it inside a public library while I dropped my books off for less then 30 seconds and it was gone. I was utterly gutted.
Your not an idiot at all, these things happen, sadly we have to develop often the painful way the awareness that we are surrounded often by not very honest or nicest of people. Hope you manage to get some kind of replacement soon.