It sounds like you have a very large battery draw. These can be difficult to find for even the veteran technician. There is no easy way to tell you how to look for it. If you have a test light, disconnect the negative battery terminal. Now hook up the test light between the battery cable terminal end and the battery terminal. A pair of vice grips on the battery terminal will secure it in place. This light should go out after about 20 minutes. All modules will go to sleep. If the light doesn't go out then you have confirmed a draw. Now for the fun part. start pulling fuses until the test light goes out. That indicates what ckt is still live when it shouldn't be. From there you need to find everything that is on that ckt and start unplugging it until the light goes out. Having fun yet?
Let me know how this goes. Hope it was helpful.
The poor idle is usually caused by the weak/dead battery resetting the engine computer and the idle motor gets really confused. It will eventually learn what it is supposed to do.
I posted a response but it apparently didn't show up. If I remember right, your battery was dead again and you recharged it but it would only "click" when you were done.
It is possible that the battery is begining to fail because of repeated discharge and recharge. I wuold suggest that you check your battery terminals for being clean and tight, then also check the ends of the cable where they attach at the block and the starter, make sure they are clean and tight. Next time you get it started get the truck to someplace that can run a test on the battery. Usually a parts store like AutoZone will do this at no charge.