You know when people are working away on a client site all the time, companies give them what's called a per diem to cover incidental daily expenses, because no-one on either side can be arsed keeping receipts for and processing hundreds of minor transactions? Yet you're meant to account for every penny. I like Random's idea of asking him to itemise his expenses too - why not?
I think the fact that you've been underestimating your true expenses for fear of reprisals is both very telling and also of course counter-productive. You have no other source of money so unless you can actually trim the cost to what you've estimated you're going to end up in debt. Which then reinforces his message that you can't manage your finances.
I think I've said this before on a previous thread but my DH is a SAHD due to long term illness. I do ask him what he's spent money on but only because I do the budget so I need to know what to allocate the spend to. He doesn't buy very much as he can't get out much but will then tend to want something big (like a smartwatch, say). We talk about when we can afford it but not if we should. No-one should have to live feeling as if they are beholden to another person in that way. That said, short of ill health I would never, ever want to lose my financial independence. I'm sure you never will again.