Sorry to hear that, its something Verizon is quite good at forcing updates and if you ignore it long enough it will just do it. I recall the Note 2 incident where Verizon pushed an update that would prevent root and the store reps were doing it to customers without them knowing it. I made them return mine and give me a new device.
Unfortunately the general rule is once the update is there you can't go back. If you have root you could run a KitKat related OS, but Verizon locks those bootloaders down so you may be out of luck.