I for some reason feel that its enjoyable to demonstrate interest, even in the situation a relationship won't work. I get it a situation that someone seems interested in me, then you have a big blocker, like they tell you they have a boyfriend or there is some other situational factor that means absolutely nothing will come of it, yet I still for whatever reason feel unsatisfied until they know I reciprocate their feelings (even if all they're really giving you is merit less hope, or seeking attention, or for whatever other reason unavailable women go after you).