I have that problem........I had to, while shooting a handgun, close my left eye, take aim, then open the eye and fire. I "worked through it" many years ago and now aim with the right eye while both eyes are open. It takes some time work it out.
On the teaching the wife to shoot..........use nothing but love, compassion, and retain the services of a professional instructor.
They know how to teach newbies better........they do it OFTEN.
Husbands teaching wifes anything that 'us' husbands do 'competently' and frequently isn't always a good thing.
I have learned this.......but I'm as hard-headed as they come.
I only say this from experience.......I do hope it helps