So basically you can't give up the stuff that's costing, or you don't want to give it up?
Are you sure, as in entirely sure, there is nothing you can cut down on?
Is it basically a certain amount & you'll be sorted? As in you're giving up what's costing you what you can't afford?
As you've not really said, I will check our finances to see if we can save. You're still adamant that it's between you working & in your words traumatising the children for life, so their money would go on counselling to rectify this. Or you basically say to DH look at their faces, do you really want to do this to your DC or will you speak to FIL?
How old is the eldest?
I'm sorry to be so blunt, we're sorting stuff for retirement, we looked at everything and realised we must be able to cut down somehow. Not only that other friends have been in crap situations, they've realised that Amazon Prime, Netflix, holidays, treats aren't a necessity.
Sure we'd all love to shop at M&S, realistically we could, but it doesn't make economic sense.
There does seem to be this middle ground of if you want to essentially be a housewife, some sacrifices are necessary. Otherwise the pot will be empty, you'll have a real emergency, then you'll be panicking.