HABITS ---------ATTRACTION
Not my thoughts, I read them in a scientific magazine.
The brain has neurons which pass current between each other as means of biological data transmission. If the same neurons get activated upon a particular sight, smell, stimulation etc., the particular current always flows through the same pathway, and slowly this leads to a particular pathway for a particular stimulation. So whenever a stimulation happens, the current takes the same pathway in the brain, and a path of least resistance is formed. This is what a Habit is.

This habit, if coupled with a dopamine centre being active, becomes rewarding. So whenever you see the person, the brain rewards u with a dope in the brain. So that leads to attraction (or some other habit). Till the time this brain center remains active, attraction remains. Whether, its old age, young age, whatever. Moreover, this attraction is the sole basis of Love. (see next post). So keep this brain centre active, and have a blissful relationship for life.