We shop x2 or x3 week, I can't get on with meal planning as I change my mind but by shopping a couple of times a week I can cook what I fancy according to what I pick up. We have a great organic veg stall and a good local butcher so I tend to base my meals around what I can get from them. I do work part time, so that allows me the time to do that.
I also batch cook every week so there is always stuff I can just pull out of the freezer. We also eat a lot of soup which is great for using up odds and ends.
Our larder is full of chick peas, baked beans, tins of tuna, cans of tomatoes etc so if life got in the way and I couldn't get to the shops we wouldn't starve.
I buy lots of frozen fish, freeze down lots of meat, chorizo and always have a good stock of frozen fruit and veg in.
We are also a 2 min walk from tesco.so if we run out if milk its no biggie.
Usually once every 3 months I do a massive iceland shop and buy jars of gravy granules, loo roll, cleaning supplies, tins, pizzas, garlic bread, chips and veg and get it delivered for free, so it saves me lugging the stuff home.