Passion is what keeps the excitement in a long-lasting relationship. Physical attraction is not the only way that people experience passion.
Deep commitment, excitement, enthusiasm, and genuine interest are ways to keep the passion going strong. If past experiences are recreated from when your passion was strongest, the passion you once felt is sure to be felt again. Changing things up and being spontaneous are ways to keep the light of your relationship kindled.
Just live each day to the fullest and be happy and the passion that we lust after is sure to bloom.