Don't ask us bozo's, ask her!
Seriously. I understand my wife enough to have kept her married to me for 18 years. She, like all women, don't think like we think. I jokingly say "they are all crazy, but the right one is worth dealing with the insanity." IF she likes a particular firearm, she will carry it and use it. If she does not, she won't be as proficient and she will not practice nor carry it. If she does, her insecurity will be a weak spot.
Women desire support and safety from their husbands, so provide as much rationale as you can and leave the choice up to her. Whatever her choice, encourage her decision. As time progresses, you may find a willingness to change platforms if you take this path. If you force one on her, you are done. REALLY!