Even though Geek and I have 3 checking accounts between us (his, mine, bill pay), there's still an implicit line at $100, not matter which account it comes out of. If whatever it is costs more than $100 and it's not necessary (groceries, medical, etc), we don't buy it until we consult with the other. (Gifts are obviously in a different category.) I think that's what's kept money troubles to a minimum between us. That and a shared belief that very little debt is necessary or warranted, and any debt is to be paid off ASAP. I think in y'all's case, it's a matter of actually getting on the same page. Y'all are in the same book right now, mostly, but he needs to be gotten up to date. Walk him through the spreadsheet. Get his input. Maybe actually seeing and understanding what's earmarked for what will wake him up. If that doesn't, maybe an agreement on what constitutes a viable loan (hint: none unnecessary to survival) and how much disposable income each of ya'll gets per month would work. (Make sure it's a true agreement, not a "yes, mother" agreement.)
I know, I'm young. Take what I said at face value and what'll work for y'all's situation.