The root of the problem in relationship lies in our inability to see that people dependently arise & dependently cease. - Sri Bhagavan
You think the other has a fixed nature & set of responses. You assume they don’t change. But the reality is everyone is changing every moment. Every personality is arising & ceasing in us, due to innumerable factors... such as food, places, situations, planetary positions & so on... keep activating various personalities in all of us. You are changing & the other is changing, all the time due to known & unknown reasons or factors, these things are beyond your control. When u can’t control them or change them in u & the other, then you would realise all inner effort is futile. As you have nothing in your control, u acquire a different kind of freedom & start learning to flow with live as it comes & wherever it takes u forward. Some things are in your hands, but most of the other factors are beyond your comprehension. Flow freely with life & in relationships, enjoy the ups & downs of flow of life. Life, people & the situations are beyond u or beyond the mind.