If it would make you feel better, maybe you should look into getting some kind of security system installed. You don't have to fork out a ton for those. If you want something cheap, you can pick up a motion detector. You can put them inside or outside and come with a monitor, like a baby monitor, which will go off quite loudly if something passes in front of it. We got one of these after someone tried to steal something out of our driveway and it worked fine.