If your wife's hand strength racking the slide is the issue, I have two very serious suggestions for her to try:
The Ruger LC380, or the Smith & Wesson M&P Shield EZ.
Both guns are 9mm chassis, chambered in .380 ACP. Because of this, they are incredibly easy to rack the slide, and with the correct self defense ammunition (Hornaday Critical Defense is one) the .380 is a very credible self-defense round.
Take her to the gun store and have her try out both.
I'm quite fond of my Ruger LCP II .380. It shoots well up to 10 yards or so and is so light and easy to carry I forget it's in my pocket. I don't really forget but its weight doesn't remind me its there every time I move or walk. The regular LCP is okay too if you don't like the trigger safety but I think your wife would prefer the LCP II with the easier to rack slide. It's a nice upgrade to the LCP and it's under $300. You would be doing her a disservice by not allowing her to try one.
The .380 is a good close up round and there are some good choices in carry ammo. The Leigh Defense .380 is my personal favorite.
380 Auto 90gr Xtreme Penetrator Ammunition