Totally empathise with this and it's really shit isn't it! And I don't think people who don't live quite so 'hand to mouth' can ever really understand!
There's a good website that was recommended on here - 'you need a budget' YNAB which had really good tips and made me look VERY hard at all my outgoings. There were a few DDs I had that I was able to cancel and even changing the date on some meant my actual cash flow improved a bit.
Also, if you have any debts that are consuming income I'd recommend getting proper advice from Stepchange or CAP (Christians against poverty, not just for Christians obviously, but a charity started by one). They can offer so much help and approach lenders to freeze interest/write off debts etc. offer budget advice or even discuss bankruptcy, which may or may not be appropriate, depending on each person's situation. Not suggesting you should do this at all, you might not have any debt, just saying that if you have SOME, it can become less of a burden with good advice.
I saved a fair bit by meal planning and wasting literally nothing, plus shopping at Aldi or Lidl as you get heaps more for the money. I eat as well, if not better, now than I did when I could afford other supermarkets. There's far too much food snobbery in this country! Food, ultimately, is just going to end up going down the toilet - why spend a fortune just to have more expensive poo?!
Meal planning and prepping means you're only buying what you need, aren't overspending at all, don't end up chucking stuff out that's gone off and also aren't looking at an empty fridge and getting tempted by a takeaway!
I understand totally how shit and how tough it is (especially at this time of year, when media and marketing forces spending - on stuff none of us actually NEED
- down our throats) but IT WILL
GET BETTER. And budgeting and being a bit creative about celebrating/gifts can be ok once the sheer panic has gone. Lots of really lovely activities are free or cheap too so it doesn't have to be all doom and gloom.
I hope you get some more good advice and check out the YNAB tips.