@Linkat,
No, the husband never asked her for anything, not even $5. He just told her he was running low on funds. I took that to mean that he looked at what he had and, as the DM stated, he ear marked what he had to use.
Ex. Say he started out with $150 till payday.
Of the $150 he set aside 60 for gas in his car. That leaves him with $90.
Of that $90 he sets aside $50 for groceries or small things that may come up.
That leaves him with $40 now. Of the $150 he has in the bank only $40 is what he hasn't designated for anything so he only has $40. He tells the wife that he only has $40 left. But now when he goes to the store to buy some groceries, he's pulling that from the $50 he had set aside. The wife sees groceries coming in and assumes he's got more money than he told her so in her mind he's lying.
The real question is, does the wife have much of a say so on his funds given that what he's spending is not coming out of the household joint account?