Sounds like you have zero winter protection for your water system
Hit your local Walmart or Outdoor Store and pick up a couple of 5-gallon camping water carrying "bags". They're cube shaped and have a faucet type spout on them. Fill with water from your house and transport sitting in tub/shower. When needed they sit nicely on a counter next to the kitchen sink or vanity in bath.
I had blown out my water system until I planned on hitting the road after Christmas. Daughter called and asked me to "Dog Sit" for a couple days. Sitting in my TT as I write this with one of those "water bag/cubes" sitting next to my sink on the counter and I use it for hand washing, drinking, cooking, etc.
Water came from home so I know it's safe to drink and when finished I'll just drain the bag, collapse it flat, and store it for when I boondock and need to transport water. I have 12 of them
A tip: Put a large bowl in the sink when washing hands, etc. Pour water collected in bowl into a pail and keep it in the bathroom for toilet flushing purposes. Will make supply go farther if a faucet is not readily available.