2004 Chevrolet Impala battery/electrical?

Came home from a week's vacation and car will not start. Replaced battery. Still nothing. The lights go on and it does everything except start. Doesn't click or even attempt to start. Was absolutely perfect the last time we drove it a week ago. The old battery charged at auto zone but dropped down to 30% immediately, so we thought that was the problem, so we bought a new battery. Any ideas?

Thanks!