Last night Tommy and I read Day 10 of The Love Dare - "Love is Unconditional". It defined the three types of love: agape (unconditional), phileo (friendship), and eros (sexual). While the most important love (agape) is offered without conditions, all three form a very important part in the equation of a happy marriage.
1 Corinthians 13:7 says, "Love bears all things, believes all things, hopes all things, endures all things."
Love is so much more than just a feeling. It is a lifetime commitment to seek the best for someone else before yourself. If it is based on conditions, eventually love will fade because as time takes its toil on our human bodies and minds, those conditions will eventually fade as well.
Take time to consider what is the glue that holds your love secure to your spouse? If it has to do with appearance, intelligence, humor, or charm, it isn't going to make it for the long haul.