It's a totally different routine isn't it? You go from including him in the cooking, to not having to cook for them. When DH works nighshift, DD and I usually have very simple meals - her favourite is spaghetti with pasta sauce.
He comes home and goes straight to bed, so DD and DS only get to see him for an hour in the arvo when he wakes up and gets ready for work.

I'd take advantage of the time and use it as 'me' time, watch a show that he may not like, or tape a show on a different night and watch it when he is at work, read a book, play a sport etc..
Try to keep your bedtime routine the same, so go to bed when you normally would. It takes a bit of time to get use to not having them beside you, but eventually you'll get there...especially when you can have the bed all to yourself