Some think of happiness as a glamorous life of ease, luxury, and constant thrills; but true marriage is based on a happiness which is more than that, one which comes from giving, serving, sharing, sacrificing, and selflessness.
Spencer W. Kimball
The honeymoon doesn't have to end, it just needs to adapt. By following the principles of giving, serving, sharing, sacrificing and selflessness, the feelings of love and joy can deepen over the years. Make the fire a bonfire rather than just smoldering embers. Just as a fire needs fuel to keep burning, so does a marriage. The fuel to keep the romance burning in your marriage is adhering to the above mentioned principles.