Lots of good gun belts for women out there, if you know where to look & what you are looking for (and why!)
First, your wife's already discovered that she needs a belt specifically designed to hold the weight of a firearm. Good for her -- that's a major step. Grabbing a belt from a discount rack, or even a standard retail shelf, won't do it. Standard belts are just too thin, too floppy, too prone to breakage. Too-flexible belts tend to allow the holster to lump, flop, sag... you name it! So you need a solid belt for both comfort and effective concealment.
The bad news is that gun belts are generally much wider than standard women's belts. That's because in order to do the job of holding the gun securely, there's a certain irreducible minimum of material that needs to be present. So you need to steer clear of belts less than 1 1/4" wide (1 1/2" is better) -- even though most women's belts are 1" or narrower. This can occasionally cause fashion problems, both because women's slacks just don't have belt loops that wide (no easy fix for that unless you're a seamstress), and because a wide belt "looks odd" since we're accustomed to seeing narrow ones. The fix for the odd look is to select a belt which narrows down in the front, sometimes called a
taper cut (or just tapered) belt.
Wide belts also tend to be uncomfortable for women because women's bodies are curved at the waist. (That's
why women's belts are traditionally thinner, btw.) The way around this width-caused discomfort is to purchase a
contour cut belt. When laid flat on a table, ordinary belts are straight. Contour cut belts, however, form a gentle "U" shape. This shape allows the lower edge of the belt to conform naturally and comfortably to a feminine waist curve.
So you want a tapered, contour cut belt that is specifically designed for concealed carry.
For my money, the best off-the-shelf choice here comes from
Galco, with attractive belts that have a nice hard finish.
If you want to go the custom shop route for the holster, look for a shop that does belts too, then describe what you want. I'm currently wearing (and loving) a contour-cut belt from
Ted Blocker Holsters. It's not tapered, but because I carry in appendix position I prefer the belt remain the same width all the way around. If I were carrying behind the hip, I'd choose tapered for sure.
Hope this helps.
pax