Greetings friend @amestyj, emotions are very intrinsic to every human being that is why they are difficult to predict, but in the subject of couple emotions are manifested in a spontaneous way when both are attracted, now to what extent a partner can affect you emotionally, it is quite difficult to know because it depends on many factors that each person can interpret. Something if it is true to be happy is not necessary to have a partner but if it helps you to carry your good situations and not so good and always needs that someone to motivate you to continue.