DH has been on permanent nights for 17 years. He works 4 out of 7 but with no pattern, although he tends to get 3 nights off in a row.
He says he only needs 5 hours sleep and over the years he has managed on less, but now he's going the other way. For the last few months, following the last working night he has slept all day, got up at 6pm, eaten a meal someone else has cooked and then fallen asleep in front of the TV between 7- 8pm. He will then sleep until after I've gone to bed, wake up refreshed and sit up until 3am before going to bed. Meantime I wake up several times because he isn't there, then he wakes me up coming up to bed. We don't have a spare room or I'd insist he sleep elsewhere.
The next 2 nights when he is at home will be the same story. He's home all day. I get in from work at 5pm and either end up making dinner or one of the kids does it. He eats, then off to sleep. To make it worse he snores badly so it isn't pleasant for the rest of us. So I get 4 evenings alone while he's at work, followed by 3 evenings alone with him snoring on the settee. When I complained, his response was that the TV was boring! There is so much needs doing in this house there is no need for anyone to be bored. I also took offence at his implication that my company is so boring he'd rather be asleep. I've been on the verge of walking out so many times because this situation is really getting to me. I understand that night work takes its toll and isn't the same but he can't (or won't) do anything else. To my mind falling asleep at the time you would normally be going to work makes no sense at all.