Sometimes, I feel that my husband doesn't quite understand. But, that's not because he's not understanding; he's just not a nurse and doesn't work in healthcare. But, even though he works a desk job, he understands what I do when I describe it to him. I've told him once or twice what exactly I accomplished in 12 hours for my patient, who I had to call to get that done, how many times I called the lab and/or pharmacy, bedside procedures, trips to OR and/or CT, radiology, and how I eat lunch sometimes at 2 or 3 PM with only 1 quick bathroom break the entire day.
After a few times, he got it. He understood that nurses do a lot, and really respects the profession. So, he never asks me to pick up OT. He'd much rather spend time with me than have me be tired all of the time (like I was when I worked night shift). Now, granted, we didn't or don't really need the extra money. That would be different, and I would volunteer to do OT then.
But, your husband needs a swift kick (not literally lol). Have you ever told him exactly what you do in 12 hours?
Ask him how he would do at his job standing at his computer all day with the phone ringing off the hook, talking to worried or needy co-workers at the same time (to compare to families), having to call IT 4 times to get them to do something they should have done an hour ago (for a report he needed to do 1 hour ago to compare to the amount of times we need to call lab and/or pharmacy), and he doesn't get to eat lunch until 3 PM with no bathroom break or no time for a quick snack.