Did you tell your wife all of your opinions face to face? I think whatever actions are taken should be her choice, not yours. Your role in all of this is to provide support and comfort for your wife, regardless of what she decides to do. However, I do agree with your point of view. I have seen several times where a dog or cat gets hit by a car, is in great pain and distress, is not going to get better, and the Thai people in my building refuse to put it out of its misery. I have respectfully expressed my opinion to them, but they disagree and genuinely feel that nature should take its course. In the future I will keep my opinions to myself.