Never be used again!

The harmony between two partners is one of the most vital parts to being happy within a relationship. But when the harmony is broken everything eventually descends into chaos, and things like distrust, constant bickering, and at some point the person you thought you loved will start to feel like a stranger. If the person refuses to walk the road to change staying with them is going to be a waste of time and energy. 

Selfishness can cause even the strongest relationships to fracture. Nobody wants to be with someone who tends to be so focused on themselves that they cannot see the relationship. That being said, the priorities in a healthy relationship should be the ability to create an environment of caring for one another because its much better to have a person who is willing to share everything with you, go through hard times with you, and love you accordingly.

Under no circumstance should you feel neglected or feel like The lone support system of the relationship (feeling constantly alone in every situation), it hurts to be taken for granted and quite simply the person who is found doing this should be cut off because that's not love and its unlikely that such behavior will change.
A person who is literally making you feel as if they have an advantage over you in the relationship will always be a bad thing.