Congratulations! God has blessed you by giving you to each other for so many years, and I pray the years ahead will be even happier than the ones you've already experienced. My wife, Ruth, and I were married for almost 64 years -- and we grew even more in love as the years went by.
I certainly hope marriage isn't on the way out in our society (although sometimes I wonder), because God gave marriage to us, and He meant for it to be a source of joy and stability and strength. And it will be, when a husband and wife put God first in their lives and make Him the foundation of their marriage. God has given us His pattern for marriage in His Word: "A man will leave his father and mother and be united to his wife. ... So they are no longer two, but one" (Mark 10:7-8).
A good marriage isn't a question of physical attraction or compatible personalities. These have their place, but most of all a good marriage is based on commitment -- commitment to each other, and commitment to God. Emotions come and go; physical attraction fades; differences can flare into anger and conflict.
But when we know Christ, we know that true love involves a commitment to do what is best for the other person. It's an act of the will -- and a gift from God. Thank God every day for His grace in your lives -- and for hope that extends beyond the grave.