Thank you for the great points.
I have crated her at night before, and she does not soil anything. But I want to trust her, which is why I leave her loose with my neutered Dogo Argentino at night, as he never soils or destroys anything in the house.
She is not spayed (yet), and she does get a reasonable amount of exercise, but she has always tended to be lazier/less active than my Dogo.
Both dogs have been eating the same kibble for over a year, and there have been no changes in her diet at all.
We were away on vacation for a week, and I put the dogs in the same boarding kennel for that week. This is the 3rd time that she has been boarded at the same place, and she never behaved like this the 2 other times. The only change in the house has been that I have put up a winter fence to block off the grass in the yard, but there is still lots of room to play/run on the patio. I put up the same fence last year, and she did not seem to be affected by this change in the yard.
I usually take both dogs out around 10-10:30 pm before I go to bed. My Dogo runs around the yard and does his business, and sometimes she just lies there or runs a little bit. She sometimes does her business, and other times she may be out there for over 20 minutes but does nothing. She very rarely does her business on walks (even walks longer than 1 hour), as she seems to prefer to do it in the privacy of the yard.