I went through this with my wife. She tried all my guns, I bought her a 9mm snubby, a .38 snubby, a 9mm auto - she liked the revolvers for their simplicity but everything was too heavy, too much recoil, too loud etc. Because of those things she didn't want to shoot because she didn't enjoy it. Finally we stumbled on a S&W 317 8 shot .22LR snubby, which she absolutely loves. It is very light, easy to handle, easy to operate, and best of all, she enjoys shooting it. All of that means that it is a gun she has confidence in and will actually carry. Would I prefer a bigger caliber for her? Of course, but I accept it as it is and I'm just glad she's armed and confident with her ability to use her gun.
"If violent crime is to be curbed, it is only the intended victim who can do it. The felon does not fear the police, and he fears neither judge or jury. Therefore what he must be taught to fear is his victim." - LtCol Jeff Cooper