Both headlights burned out tonight... Why?

[Green Monster]

Okay... so I charged at 2 amps overnight on Monday night. I checked the Tuesday morning and the battery was still taking 1 amp. So I pulled the plug on the charger. I put the battery on a 6 amp charge tonight and it is taking 4 amps. I will check it out tomorrow morning. I disconnected the positive wire from the battery during charge because I don't really understand how I lost the charge in the battery to begin with. I'm afraid I may have a short somewhere. I would hate for my house to burn down because of a wiring issue in my beloved Blazer.

The wires look good. I checked them over. I will investigate further when I have more time. Probably Friday.

I'm just curious why my battery was drained. Yes it is a about 4 years old, but typically they die slowly, not just overnight... right?