Being lustful is the most important and mandatory need for every individual if he wants to enjoy the pleasure of Orgasm. It's God gifted and starts to thrive in teenage, although they are present in the brain since childhood.
Love is totally spontaneous and happens just in a natural way. We can't control it. On the other side, Lust is a natural thing that everyone has for the opposite sex. Not only in human beings, it is also present in the other creatures of the Universe.
This is so simple. You do not need to search. You do not need to quest. You do not enter the phrases like 'how to maintain the relationship' in your Google bar. You do not need to remind the rules. You do not need to mix it with artificiality. You do not need to change anything.