Only changed the pads in my juicys once in a years and 3 months, that was only the front also. Back is nearly ready now. The bike gets abused, mega rides, fast DH stuff also, rain, snow, sand, salt (well once) never had any “go” on me in a couple of hours.
Sounds like your doing something fundamentally wrong, and i would say that is the bedding in issue.
I said this in a bedding in thread, may have been yours, but all i do i squirt water on them ride stop, and keep doing that till they stop me very suddenly. Sorted!
Also after riding the cross bike off road in the wet and mud last weekend, with that horriable noisy Vee brake noise, no power. Discs are the future,