I'll ask this....
Would you let her go pick out a tool set for you? Or a chainsaw?
Guide the spouse, but ultimately, it's THEIR decision. Heck, you pick up a box of ammo, I'll let her shoot our revolvers is she wants. One's a 2", the other a 3". As to terminal performance, Rule of 3's here. 3 feet, 3 shots, 3 seconds. Incident is over. If it's a bedroom gun, range of what, 2-3 yards or LESS.
Want to convince her at that range a semi is better than a revolver, hold a hotdog next to a cylinder at the front when you fire it. Because at close quarters, SOMEONE's skin is going to be next to that spot. It's likely to be a belly shot or an indexed. And you DON'T want a revolver next to you when that happens.