First off, congratulations on 40 years! not many can claim that these days.

If she is a good shot, then she doesn't need a canon to get the job done. Whitetail can be taken with a lot smaller ammo then a 30.06. I killed 2 whitetail deer this year with a .223 at over 200 yards with the Winchester Power Max 64gr. Both were clean pass throughs at that range and both deer died pretty fast. I have killed many deer at 300 yards with my .243 (actually it's my wife's gun, that I commandeer because it is a nail driver) shooting a Winchester 100gr PowerPoint. Iv'e never had a single deer walk away from a shot with my wife's .243.

Watch this video to see the damage the .223 had on a whitetail buck at 170 yards.

my lady shoots my old remington 700 270. She also shoots my new 300win mag, but theres a catch. My 300 mag has a muzzle brake, she and I both swear till we're blue in the face that the 300 kicks less than the 270 with the brake. I don't know what your budget is so its hard for me to recommend a higher end rifle something upwards of 3000 without glass so i will say something around 270 should be perfect, its killed deer from 2-300 yards forever. But if you want to spend a little extra on a custom rifle, i am now enamored with the 300winmag and highly suggest this cartridge, just make sure its got a brake or its definitely going to feel like a 300mag lol. Plus it gives you a wider range of possible game than the 270 IMO, i mean you can kill an elk dead with a 270 i just think its a better option to go with something bigger.