I got back into shooting a few years ago when we armed our 24 year old daughter who had a stalker issue. She went and got a CCW, an injunction against the dirtball and has not had a problem since.
I used that to get my wife to agree that we should have a gun at home. She was not anti-gun, just not comfortable with them. I got my carry permit and started carrying. There were times she would say things like; "you are carrying here?" I would ask if she could guarantee there would not be a problem here. Since she couldn't she dropped it. Then came Aurora, CO and now she knows what I mean, and often asks if I have a gun with me. Which I do.
Try talking with her about places like Aurora, or Newtown, CT, or VA Tech, or the McDonalds in San Diego many years ago. You don't expect an issue in those places, but those places certainly point out places that might have turned out differently if someone had been armed.
A bad day at the range is better then a good day on the job!