This might not be the answer you are looking for, considering I really have no idea of what your winter conditions are like where you live, but this is what I do.
We use our Montana (actually all of our previous travel trailers too), year round. And we live in Indiana where temperatures can get down to -20 (yes... below zero). Last winter it got down to -10 a couple times. In other words, from December to the end of March, we can expect below freezing weather. But that does not stop us from using our camper.
When we are not on the road, we practically live in our camper in our drive way. We simply do not use the house, we enjoy the camper that much. And we are in a position where we can use the camper at home.
However, when November rolls around, I'll do the full winterizing process, including cleaning black and grey tanks, winterizing with the pink-stuff, everything.
Inside the camper we use a port-a-potty and will dump it inside the house or directly into our septic tank (which I can do with no issues at all). We keep 5 gallon jugs of water in the camper and catch all water in a tub kept in the sink for washing dishes.
However, we do take showers in the house during this time.
Except for showers, we still cook, eat, sleep, and play in the camper with it completely winterized.
I know, you are saying, but isn't your Montana good to use to zero degrees without pipes freezing, and doesn't it have tank heaters?
Yes, you are correct. But it takes an incredible amount of propane to keep the underbelly heated once temps reach about 20 degrees or less. We supplement the furnace with electric heat, the fire place and a couple space heaters. Once the propane usage reaches 1 - 30 pound tank of propane every 2 days, we move back into the house.
What I'm suggesting is, if you really do not want to go through the process of winterizing and unwinterizing ever time you visit the camper, then winterize, and when you are the camper .... dry camp.
Once you force yourself to not use any water through the camper's water system, and once you find alternative methods for your water consumption and disposal, you'll find you can really, really enjoy your camper .... even in the coldest weather.
Anyway, it's just a suggestion, and this is how we do it.
(we have on many, many occasions winterized and unwinterized up 4 times over the winter. Why? Because we take off with the camper from Indiana and travel South during these months, and then return back home. A couple years ago, we did this 4 times over the Winter months. We unwinterize once we get out of the freeze states and winterize again when returning back to frozen Indiana.)
To plant a garden is to believe in tomorrow.
2019 Montana High Country 375FL
2014 Chevy Silverado Duramax, 6.6L Dually