I had an extended wait for an appointment with our GP Practice Nurse yesterday and whilst idly gazing at the notice boards (as you do), I noticed that there was a prominent one for those who are unpaid carers, with some information about accessing a locally available discount card, supported by all sorts of businesses. It seems it's part of a Mencap project, but is available to any unpaid carer who is caring for an adult over 18.
Nosy as I am, I had a look online at its website, and there were quite a lot of well know businesses signed up to the scheme, most offering a 10% discount on a range of things from goods to meals out. Sadly this particular card was specifically for carers who are resident in Southampton, but a further online search revealed that there are others. It might be worth taking a look online or on notice boards in your area, to see if there's one available where you are, because, as a certain supermarket chain is always telling us, "every little helps".