Car wont turn over and no power at all

Hello everyone.
I have a 1994 cavalier 3.1.
On Monday my car wouldn’t turn over, and had no power at all so I replaced the battery since it was fairly old. With the new battery installed everything seemed fine until Thursday morning when it wouldn’t turn over and had no power again. I assumed it must have been running off the new batteries juice Tuesday and Wednesday and finally ran out on Thursday so I changed the alternator, recharged the battery and it seemed to run fine.
Well the following morning it wouldn’t turn over and had no power again. I went ahead and jumped the battery and drove it to work with no problems, but when I took my lunch break five hours after parking the car it wouldn’t turn over and had no power once again.
I jumped it at the end of the day and drove it home without any problems. I went out a few hours later to see if it would start and guess what? I checked the battery to see if it had any juice, thinking that maybe it had a short that wasn’t allowing the electrical components to work but the battery was dead. Maybe something is drawing the battery down while its shut off or the new alternator wiring may have a short or possibly a relay switch or something. Anyone have any ideas? Thanks any advice is greatly appreciated.