If you have been married or together for 20 years, I would like to assume that there is a pretty deep seated trust in your relationship. If so, maybe you can approach the subject from the caring side. You already know that she has an issue with guns so appeal to her sense of self preservation, like you said, the world is a different place today. Find some instructional videos on the Internet. The USCCA website is a great resource for gun handling, education and it shows real people, many of them women that carry weapons and shoot competitively. I know my wife became much more comfortable by watching the videos and gaining the knowledge of gun safety and different types of guns. Ask her if she would like to go to a range. Find one that rents guns so there is no commitment. Maybe at first she could observe you or others shooting from behind the glass. In my experience, once you can show someone that it isn't the gun that is the issue and that the operator is responsible for the guns actions, they eventually become more comfortable. You could even start out with a BB gun plinking at aluminum cans to build her comfort level. Then move up to a .22 pistol and so on. Luckily for me, while my wife had not done much shooting, her family is a hunting family so she was around responsible gun owners. I wish you all the best on convincing her to at least give it a try. I think if you can do that, she will come around. My wife and daughter love to shoot now. I just bought my wife her first gun ever, a Sig Mosquito with purple highlights, that's her favorite color.
I am not politically correct. I am all about the facts, I am all about the truth and I am all about Godly pursuits and what this country was built on, and I am not apologetic about it. - Luke Scott