I cannot get into a lot of specifics because I don't personally have a winterized camper but I do know that it can be done, and done comfortably.
My brother-in-law is a high voltage electrician and travels extensively due to work. Years ago he gave up on living in hotels and bought a tow behind camper (he's now on his third, as he keep going bigger) and has used them all over the US, including the northern tier, through many winters. This winter he is in northern Ohio and its been cold there. Lots of snow too.
Some campers are made for this (more insulation than is typical and the various tanks are inside the heated envelope), you will have to look more into yours for details, but as a concept, it is very doable. My brother-in-law loves it. For him, its a home away from home and no more living in hotels. He finds a campground that will do a year round hook up (not always easy he says) and generally gets extreme discounts for out of season time.
Heat tracing service lines is of course critical.
I look forwards to welcoming you back. I too left for awhile but only to New Hampshire as all of my work is in Mass (I WILL NOT LIVE THERE) and originally came from the Bangor area. I'm in southern main now, but still in Maine.