Budget Blues

Oh, god, I'm going to talk about money.
Let me be clear about something: I'm not really very good with it. My feelings can best be summed up as "if I has it, I spends it." Of course, there are people out there who are much worse than I am - I'm not actually accruing any debt or anything - but I'll be the first to admit that I'm terrible at saving.
I know I've mentioned the furniture business Brian and his brother started, but something that I haven't talked much about is how upset Brian has been lately that he can't spend as much time as he'd like working on it. They've been having some success, and I know he's felt like he's not as much a part of it as he'd like to be. They're doing commissions, collaborating with artists, and getting their pieces into stores, and he really wants to be there to help it keep growing.
I told him a while back that I would help him even if he quit his job, that we'd find some way to make things work. Thankfully, he's not doing anything that extreme, but he is moving to a part time position and will be making about half of what he currently makes. Cue mild panic on my part.
The Prince and the Pauper
Ok, yes, I know I told him that I'd support him, we'd make it work, blah blah blah. He's still going to be able to pay his portion of the rent, but after things like transportation and his cell phone bill, he's not going to have much of anything left over. Our utilities are included in our rent, so yay for that, but I'm going to be taking over all of our other household expenses, like groceries. Since he won't be able to buy his lunch anymore, which he currently does most days, I'm going to have to cook more and bigger meals to make sure there's food around the house.
Don't start with me about feeling like I have to cook for him. I like to cook, and I'm also kind of anal retentive about my kitchen, in that I don't really like other people using it. I'll shop and cook, he'll do the dishes, everyone will be happy and fed. I'm still a good feminist, even if I spend a good portion of my time barefoot in my kitchen.
We sat down and figured out what our expenses are, and after everything, I've still got a little bit left over. Enough to go out for dinner once in a while, or buy a new skirt or dress clip, or buy my coffee on a regular basis. Not all of the above.
Not quite where I'll be at.
I'm going to have to start making some smarter choices about how I spend my money. I like to buy things, and not spending money on things that I want, but don't necessarily need, is always a struggle for me. I'm sure I can adapt to my new budget, but I also know it'll take some time before I get used to the new status quo.
I guess it's a good thing, in a way. It's easy to be stupid with my money when I have extra. I don't think about my purchases as much, and when I buy something, a lot of the time it's with an air more of "why not?" instead of "why?" I'm also kind of excited to be cooking more often. It's something that I was really passionate about for a time, and while I still cook regularly, I don't put a lot of thought into what I make. You'll definitely start seeing recipe posts here more often.
I hope I don't sound terribly entitled. I grew up pretty poor, and now that I have enough money not to be struggling all the time, I really appreciate it, and it's going to be hard to start watching my pennies all the time again.
How have you dealt with budgeting difficulties? Is there anything that you recommend to help avoid missing spending money that you don't have anymore?