You notice the last part of my post was "(and yes, it works in the other direction too)".
A relationship works when each party values what they get from the other, and considers the cost of keeping the other happy to be more than worth the benefit they get from the work the other person performs to make them happy.
A relationship is in deep trouble when one or both parties decides it's too much work to keep the other happy.
[A relationship is in deep trouble when one or both parties decides it’s too much work to keep the other happy.]
True. It also indicates a lesser degree of love and caring.
I grew up watching a most perfect love story - the marriage of my parents. There was never a fight, an argument or a sharp word spoken. Frankly I was unprepared for real life, lol.