Good for her. I made the same decision 5 years ago and aside from eating loads of cottage cheese and flaxseed oil - I've had a largely painfree and completely normal lifestyle. Maybe more than normal raising a family of 2 teenagers, running a high stress business and stealing time to work out.
If she wants to see what she's been missing she can go to a cancer ward in a year and look at the shape those poor unlucky souls are in that couldn't take the pressure. Think she'll regret her decision then? Me neither.