We spend about £25 a week on food and have some lovely meals, but they wouldn't suit your partner's taste at all as they involve a lot of things like veg/potato curry, pasta & sauce, soups and vegetable or fish stews etc, all made from scratch, mostly vegetarian with the occasional fish or seafood meal. We can't afford to be too fussy right now, and £1.20 on fish fingers would be wasted money - I could do a curry lasting for 3 days with that money (apart from the spices which I already have in the cupboard) - a few spuds, an onion or two, a few chillies and some tomatoes or a tin of tomatoes. Our blow-out meal this week was a fish pie which cost about £5 to make and lasted for 2 mealtimes for 2 people.
I think often there is a gap between what people would like to have and what in reality they can afford - most of us experience that. But your partner needs to come to terms with the fact that his income can't finance a roast dinner with all the trimmings or whatever else takes his fancy every night. He has to realise that isn't going to happen, however great your or his cooking skills are - and broaden his tastes and his mind to fully appreciate the huge range of options that are available on a lower budget.
I have to say though that I really enjoy cooking, and I especially enjoy cooking for my partner (he works long hours and I work part time with periods of not working, so I do all the cooking, I like doing it so it's not even a chore to me) - if he didn't appreciate and enjoy my cooking, I don't think we'd have stayed together! There was loads of stuff he didn't like (rice dishes were his particular bugbear) when we first got together that he now appreciates, because that's what I like to eat, so sometimes I cook it, that's what is on the plate, so he eats it, and finds he enjoys it. We rarely eat ready meals or processed food, only occasionally when he's done a double shift and got home really late and I'm suffering from fatigue, in which case we break out an emergency frozen pizza. Other than that everything is cooked from scratch.