Go with the .357 and load it with .38 specials for your wife. You might like the Ruger SP101.
I have a 3” barreled Stainless Smith and Wesson .357 loaded with .38+P ammo for the wife in the bedroom safe. It sits next to my Glock 21 .45 ACP with two extra mags. I would consider getting the short barrel for your wife as it is harder for a perp to wrestle the gun away from her and the shorter barrel length does not matter so much at the ranges the gun will be used. The drawbacks to the short barrel is greater muzzle blast and a shorter sight radius.