Hot states with odd cold snaps seems to be a battery kryptonite. They last 3 years or so down here in Florida. My original battery went from strong and fine to dead in one drive. Started up to drive to church to turn on the sound system, took 2 minutes and ran back out and it was dead. They are fickle thats for sure.
I have an impossible time understanding you have a 10 year old battery in your truck. Id love to see a picture of it to see its manufacture date as Ive been around cars my entire life and yours would be the first battery Ive seen last that long.