The XDs is single-stack and has the great XD firing system. It is 45acp, however, which will feel quite a bit different from 9mm. Plus, out of that short barrel, 45acp is really bright/flashy. I am not a fan of teeny double-stacks like the 3" XD9. Width is much more important than length for carrying.
Really small pistols are going to kick a lot regardless of caliber.
Small thin grip makes recoil feel worse because less surface area to spread the force generated.
Best thing is to finda range that rents guns and have her try a selection.
"Gun control: The theory that a woman found dead in an alley, raped and strangled with her panty hose, is somehow morally superior to a woman explaining to police how her attacker got that fatal bullet wound." L. Neil Smith
The problem with being stupid is you cannot simply decide to stop doing dumb things...
Kahr has a funky pull so if she is new to shooting I would think and hard about that. Glock makes several good options but again you have the funky trigger issue. Take her to a gun store and let her play with a few of them.
I picked up a 2 shot .22 magnum for her she liked the sig p220. And walter PPK she said the karr felt weirdand the G26 was to fat ..I don't like the darenger .22 mag so I will keep looking..but she has something to keep on her wile she is at home alone and that makes me feel a lot better