Do what I did: get her a Kel-Tec PMR-30 in .22 WMR.
The PMR-30 shoots like a LASER. She likes it. NO RECOIL. Light, comfortable. And ours with low mileage has been very reliable, and most users over the past year or so claim GREAT RELIABILITY from theirs on these forums. (There's a BIG BOOM and flash so warn her!) First time out was hitting well, at 15 feet -- and for her that was a big psychological boost.
(The Hornady self-defense loads, designed for handguns rather than rifles, perform a lot like .380 rounds!)
The only downside is ammo cost --but .22LR isn't all that cheap any more, either. But, you can get some rounds for around $12 a box (for practicing); the more costly SD ammo is anywhere from $13 - $16 a box.
My wife wanted something for self-protection if I wasn't home, and nearly every other gun we tried -- and we tried a lot -- was not well received.
(She could handle a smooth, tuned revolver, but couldn't hit anything. She could hit with some semi-autos, found recoil a concern, and if there was a jam and she needed to rack the slide, it wasn't going to work. And, yes... we tried many of the different ways recommended for weapon to rack slides. Zilch.)
If your significant other =shoots it well, and she probably will, and ever needs to shoot in self-defense, 10-15 hit (of those 30 rounds in the mag) can do somebody a lot of harm.
The problem is you'll want to play with it yourself...