If you like eating meat but want to keep costs down, think not only about how often you are eating meat, but also how much meat you are eating at a suitting.
4 chicken breasts is at least 2 meals for 2 adults and two huge and ravening teenagers in our house. Curry (with a couple of tins of tomatoes, half a pack of value peppers and a couple of onions, plus some curry paste and a spoonful or two of yoghurt, or with green thai paste, muchrooms, green beands and coconut milk, plus coriander) served with rice can feed 4 of us with 1 or 2 chicken breasts. Chicken kebabs with lots of veg between the chunks and a good pilau rice with pine kernels similarly.
Equally, we buy very nice mince but our bolognese is a primarily tomato and vegetable based affair with some mince, then we add beands, chilli and cumin to serve the next day with yoghurt, guacamole, wraps and salad, then stretch the mince mixture with more tomatoes and veg such as aubergine or courgettes to make lasagne.
A 1.3 kg gammon joint will serve us roast, cold with baked potatoes and a lentil salad, then either with mushrooms and cream in a pasta sauce, or added to a Sopanish omelette.
It also makes meal planning really easy - start off with 'main meat for the week', devise the 2 or 3 meals from it, then add a pasta and sauce dish, maybe a baked dish such as a quiche or pie, a curry if you haven't done one from the main meat, a meal with fish or sausages - and you're done.
We spend an average of £90 a week on everything, including lunches for all 4 of us for a week. Bit less in summer because we grow our own veg.