No product will "get rid" of scars, especially after three years--there are products designed to minimize scarring, but the jury is out on whether they really work or not. So many things factor into how a person scars, so there's not more than anecdotal evidence if the scar products work or not, AFAIK.

The real question is if your wife is self-conscious because her scars are really worse than what's to be expected, or if the problem is that she can't accept normal scarring. She needs to see a plastic surgeon to get the scars evaluated. If they're raised and very unsightly, or she has "dog ears" at the end of her scars, scar revision may be possible. It depends on what the surgeon thinks, although she can always get more than one opinion. The scars hopefully would heal better, thinner, and less visible, although they will always be there. But if she has normal scarring, then the main problem is her perception and to help that, psychotherapy may be needed.