It may not be as much work as you think. My 12 yr old DD turned veggie just over a year ago and has stuck to it. My other two are confirmed carnivores as is my husband!
Here are some of the things we do that everyone will eat:
Brie risotto, onions, garlic, rice, veggie stock then mix in a big chunk of brie, top with cranberry and you can also top with a bit of bacon for the meat eaters
Carbonara, make a carbonara sauce with eggs, cream, herbs, garlic and cheese, put aside a porting for the veggies then mix bacon into the remainder for meat eaters. I sometimes stir veggie bacon into DD's but not always
Egg and chips!
Lasagne and cottage pie made with soya mince, honestly with good seasoning and lots of cheese mine don't even notice
Jacket potatoes as you can have lots of toppings
Pastries made with a pack of filo pastry, feta, cous cous, sultanas, garlic, onions, seasonings and any leftover meat for meat eaters
Sausages and mash - just substitute veggie sausages where needed
Bolognese, make a tomato sauce first, put aside a portion to mix with soya mince, mix the rest with meat for everyone else
I have a few freezer veggie staples in to replace meat for Sunday dinners etc, Sainsbury and Asda are both good sources.
Good luck, it will be fine!