In romantic relationships we walk a tightrope between giving up too much of our existential freedom and not giving up enough. If you fall too far on either side the relationship will probably suffer. How do you maintain a separate sense of Self while at the same time authentically connecting with your partner?
The tendencies to grow and self-actualize on one hand and to fuse with someone or something else on the other have different strengths in different people but they exist in all of us. These competing existential pulls are largely unconscious processes in the context of many relationships but they exert a profound influence.
Probably the biggest psychological reason to fuse with another human being or some other structure is that it lowers existential anxiety. Without any uncertainty there is no reason for anxiety. As conscious, intelligent, separate beings we all feel the temptation to slide back into the preconscious state of our existence where we were fully connected to nature and didn’t have to make any choices. This is our shared evolutionary history as human beings but also your individual history as a fetus in the womb, physically connected to another human being and symbolically floating in the primordial soup. This human yearning is expressed in the story of Adam and Eve, where their sin was becoming consciously aware of the difference between good and evil, losing their sense of oneness with nature.
Many individuals search for relationships where they can give up their individuality and fuse with someone else in order to lower anxiety and symbolically go back to the preconscious state discussed above. The problem is that they give up their rights to self-actualization, to becoming who they really are, and some part of them will always be aware of it and whisper in their ear that they are betraying Self. The decision to merge with another and derive Self from an entity bigger than you is a decision to move backwards in human evolution. This is why it can never be fully gratifying and why it only temporarily reduces anxiety.
On the other hand, none of us can be happy unless we feel connected to other human beings. A state of total psychological isolation is a state of insanity. In our culture there is no human relationship more conducive to feelings of connection and intimacy than the romantic relationship. At its best it provides a safe space where people can feel loved, understood, and supported and where they can derive a sense of strength, comfort, and solidarity from the setup. Like we said problems can arise when people attempt to fuse fully and give up their individuality, but they can also arise when one or both partners feel it necessary to maintain total independence and a sense of Self at all costs. They worry about being controlled and are usually pretty obstinate, even when what is asked for is reasonable or a relatively small concession.
The rub is that you cannot fully become who you are in a vacuum. We are social creatures and our sense of Self is ultimately a Self related to others. Just raising your conscious awareness about the powerful competing human needs in all of us to increase independence on one hand and to give up independence on the other can help you see a lot of the confusing conflict in your romantic relationship for what it actually is. The ideal from a psychological point of view is to create a space that honors both of your rights to growth and self-actualization within the space of your shared relationship. When you are authentically concerned with helping each other grow and become who you really are feelings of connection and solidarity automatically increase. Neither of you feel trapped because the supposed confines of the relationship are actually the wings of existential freedom.