Infatuation is instant desire, one set of glands calling to another.
Love is friendship that has caught fire.
It takes root and grows, one day at a time. Infatuation is marked by a feeling of insecurity. You are excited and eager but not genuinely happy. There are nagging doubts, unanswered questions, little bits and pieces about your beloved that you would just as soon not examine too closely. It might spoil the dream.