2006 Subaru Forester (Automatic) - Car not starting, loses power after turning key.

My wife's car, a 2006 Subaru Forester, stopped starting up yesterday morning. I have previously replaced the alternator about a year and a half ago and the starter two months ago. I have charged the battery and this does not change the outcome.

What happens:

1. Put key in ignition

2. Turn key to start

3. Loud click

4. All power to the car dies.

If I leave the car alone for a few minutes, the power returns, but when I try to start the car it happens all over again.

The car was driving fine since I changed the starter.
I am at wits end with this and I have no idea where to go from here. Any help is greatly appreciated.