A trip to the vet to rule out an infection or physical abnormality would be a good idea. If there isn't anything like that going on, try stretching out the time before taking her out. Instead of one hour, try an hour and fifteen minutes. If that goes well, stretch that to an hour and thirty minutes. Once she's adjusted to the new interval, stretch it out a bit longer.8+ hours huh? My pup has a bad habit of peeing every hour, even though it's barely anything. Kinda weird that she doesn't normally hold it for a while, just pees the tiniest bit as soon as she can. I might have to just take her out in the front yard every now and then with a harness and let her do her thing like that, it's exhausting managing this one with these Chihuahuas around, they're mean. And my husky is a good girl! I never liked Chihuahuas lol
My GSD was well over a year old before she could hold it for more than six hours, but eventually she matured, and no longer needs an early morning potty run. It just took patience to get her there.
And I've met some lovely Chihuahuas.