I recently read that 80% of men who die are married and 80% of women are single. One reason for this is women live longer than men. When a couple marries, the man dies first, as a married man, and the woman dies later as a single person. (Widows are considered single.) As I looked into this further, I discovered that a widow, male or female, is 66% more likely to die within the first three months after their spouse's death.
Based upon the above, if you are a man, who is likely to die first, and you are leaving it up to your spouse to take care of all your estate planning matters, there is a good chance that your spouse may die within 3 months. That is a small window to allow them to take care of all of your and their estate planning needs.
The best strategy is to make sure all your estate planning needs are resolved when you are both healthy. That includes your Will, Health Care Proxy, Power of Attorney, Living Will, and Trust. That way, if tragedy strikes twice, your estate is protected.