Heeding to hear something over and over again is a sign of insecurity, whether with life in general or just the particular relationship (though the two tend to go hand in hand).
Sure, it's nice to share your feelings, but when it gets into a score-keeping scenario like this it gets unhealthy.
Show your love, words truly are cheap, and when they're used over and over again they can easily lose the special meaning. For example, replacing "bye" with "love ya' on the phone... it becomes mechanical and loses it's meaning. you could be saying 'purple bug' and it would mean about the same thing.
Focus on showing your love and caring for the other person, not just vocalizing it as a continuous reassurance.
-- Dan