"Let me not to the marriage of true minds admit impediments" -- Wm. Shakespeare
Relationship is hard-wired in us. We couple in marriage, but that is not the only example. Taking it out of the realm of sex, we couple informally with friends, business partners, and children. The first thing we do in this life is to bond with Mother. An infant who is unable to do this fails to thrive, and may even die. Relationship is vitally necessary.
And yet it does not come naturally. Relationship is not static, rather it is an ongoing process of learning each other. Marriage, friendship, and parenting all need attention in order to work well.
Whether you come to therapy as an individual or as a couple, you can be pretty sure that the struggle that brought you here has to do with either your important relationships or with the work you want to do. (Too often, the two seem to collide.) Seeking help for yourself may well improve both. Seeking help as a couple will help you clarify your shared struggle, and learn things your parents never taught you.