Well, if anger has failed with the kids and DH, then go on strike. Don’t wash the clothes, don’t vacuum or pick up after them, don’t do a big food shop.
When they ask for dinner, say you are too tired to shop, they can eat cereal. Tell them you had a sandwich on the way home from work already (make sure you do). When they say the milk and cereal runs out, tell them to make toast or pasta. Be perfectly pleasant, just smile and say, “you know what, I’m just exhausted. You can sort yourselves out for a bit, I’m sure.” If the kids ask for money for takeaway, say no, you don’t have enough. If they want food, tell them to put together a shopping basket online and then you’ll check it and pay for it. Make sure it’s delivered in the evening when they are home to pack it away.
Same with the laundry. Simply do your own and say nothing. When someone complains, say you just don’t have the energy to do it all.
And then, put your feet up, do nothing at all. Sleep, read, watch tv
It is important that you are seen doing absolutely nothing productive to drive the message home.
Keep this up as long as necessary.
If they shout and say they hate you, say that makes you really sad as you love them to bits. But you have no energy left for arguing, so would they mind please leaving you in peace if they have nothing nice to say?
Absolutely cool and calm.
Oh and tell the 21 y.o. you expect rent each week. Set an amount, starting immediately. No free ride for adult kids.