My wife's friend who is about your wife's size tried a Kahr but had real trouble racking the slide. My wife also had difficulty with the slide and it really has to do with hand strength, rather than other variables. We finally settled on a revolver...the Taurus 627(?) tracker .357 with a 4" vented barrel that cuts back on the recoil considerably. It holds 7 shots and a double tap with two hollow points would be sufficient to cause a bear to think twice. The only thing we had to change was the grip. My wife's friend also went with a revolver, a Colt, that she is able to handle easily. I'd suggest you and your wife visit your local gun shop and try a variety on for size.
Useful info.
Thanks.