I completely feel your pain--especially when it comes to buying healthy food that ends up going bad in the fridge, about not knowing where to start, and about having a spouse who doesn't have to worry about what they eat!
Anyway, when I was pregnant with my daughter, I gained over 60 lbs. I wasn't really skinny before that, so I was definitely FAT. I didn't have the money for a nutritionist, or even a gym membership, so I just started buying
Oxygen (the best of all women's fitness magazines, I promise) and doing a pilates video in my living room. I went on a clean diet and exercised 4-5 days a week for about 40 minutes, and I used the Oxygen forums to get advice and inspiration and stay focused, and I lost over 50 lbs (in less than a year), without stepping foot in a gym even.
Now I can afford the gym, which is nice, and I would suggest the gym for anyone who can afford it (over working out at home, which can be hard to get motivated for, even with the best intentions).
If you can afford a nutritionist, even just for a couple of visits, do it. If not, there are a lot of great resources out there.
Just please please please don't read those phony-ass "fitness" mags with movie stars on the covers for advice--Oxygen features fitness professionals as cover models, and never has crappy advice from supermodels or anything like that--none of that "use your own soup cans to tone those biceps!" articles either, ew...
(And get your husband on board--if getting fit and losing weight is really important to you, he should do his best to be supportive of that. But he can't do that if you don't ask him to :).)