My wife doesn't worry about it. I buy, sell, and trade pretty regularly, so there are always guns going in and out of the house. The majority of my purchases are financed by sales and because I try to buy right, I usually do pretty good when I sell. Heck, almost everything I've put into my '66 Thunderbird, from the initial purchase to all the repairs, upgrades, and modifications, has been almost completely paid for by gun sales.
In addition, she has a bank account of her own that money goes into every payday that is hers to with as she pleases. I don't know how much is in there, what she uses it for, and I don't ask. Finally, and this is important, she is like purses - Coach, Dooney & Bourke, etc - so a couple of times a year I'll get her a surprise from one of those places and that helps, too.
ETA: Oh yeah, one other thing, if you can't really afford it don't buy it. Nothing -CENSORED--CENSORED--CENSORED--CENSORED--CENSORED--CENSORED- a woman off more than being irresponsible with the money that puts food on the table, a roof over her children's heads, or clothes on their backs.