I have tested the battery and it is okay. The issue is that when I turn the key I get no electrical response. We used the car last Thanksgiving. Does the car shut down something else when it is idle for so long? What should I check?
I would take the clamps off of the battery posts, clean them, then re-cinch them down. I would bet one or both of them has lost connectivity either through some light oxidation or whatever. If you aren't getting any connection and no power to any part of the car, there has to be an issue with getting power to those bits and pieces.