Being a carer means I often get too tired to cook at the end of the day - but not too much time to cook earlier on either!
I make lots of one pot, main course vegetable soups to freeze when I can. I use one large saucepan and cook (on the hob) 4-6 oz. of red lentils (which cook more quickly) with root and other vegetables of my choice - or whatever veg is left over! If desperate, I don't even bother frying, just chop up the onions, leeks, carrots, celery, potatoes etc (whatever is to hand, fairly small pieces), add a tin or two of chopped tomatoes, two cans full of water and a Knorr chicken or vegetable 'stockpot' (available in most supermarkets). I also add some dried herbs and a couple of crushed garlic cloves, bring the mixture to the boil, turn the heat down and let the whole thing simmer gently with the lid on until all the vegetables and lentils are soft, keeping an eye on it and adding water if the mixture becomes too thick. Then I season with rock salt and freshly ground black pepper to taste. If I want something more substantial, I will add a tin of cooked chickpeas at the end, and sometimes a small tin of sweetcorn, sprinkling the whole thing with fresh parsley before serving.
This makes one decent meal for two and one meal to freeze. Possibly more if you serve it with some decent wholemeal bread and some cheese (assuming you don't have to have a wheat and dairy free diet.
My mother was not a confident cook either. I (and my friends who also now like cooking) only learned how to be after buying Delia Smith's books. She doesn't assume you know anything!
Good luck! 
Lost - I thought forever - but found during a clear out!

