I have the feeling this thread has turned a little ugly.
As I understand it, this person has had 2 pets run over and killed because they were loose on the road. True, there are some personal responsibility issues here but that doesn't lessen the loss felt over a beloved pet.
I would encourage her to not own another pet until she is willing to provide proper safety but this doesn't mean I can't feel some degree of compassion. Condemning her is not exactly taking the high road. She is already hurting and there isn't much benefit to be gained by making her feel even worse.
Jix, I hope you can just hold your wife and tell her you are sorry she lost her dog. Right or wrong, husbands and wives should be able to turn to each other for understanding, support and forgiveness. She needs to know that you will be her refuge.