I agree you could flop and chop. With price as an issue, it is the cheap way to change the handlebars. But that gets you bullhorns not mustache bars, and that's not the solution to her problem. (edit: Glad you pointed that out Bat56)

Absolutely agree with all the sage advice that you have a fit issue not a style-of-handlebar issue. It's possible that raising the stem will work. It's also quite possible that you need a different stem with a different angle and/or length. There are cheap stems out there (<$20). If you need to go that way, at that point you can change your handlebar clamp size to whatever you want.

Getting carried away extrapolating some more:
1) with better fit bars, you may wind up using the drops sometimes (e.g. headwind, or just the occasional hammer), so don't dis' 'em so fast. They are certainly very versatile. Worst case, the drops aren't doing any harm, why should you care if there's a little metal dangling down there?
2) like you, I have drop bars and I ride on the flats a lot. I really like my cross levers. They're a cheap add, probably $$ better spent than screwing with other bars unless you want to go the often style-driven route of bullhorns, mustache, etc. +1 on probably needing a stem change with a move to mustache bars.
3) There are also some very un-stylish touring bars that may give you more comfort.