Life seems almost impossible without the pair-bond with this other person. Without your realizing it, these feelings of romance are, unconsciously, like a romance-type dependency of child-parent, but they are also a new, unique, peer pair-bond seemingly without compare.
A period of self-awareness and life-change occurs for the couple as they repair their anger/anxiety (or other) cycle, stabilize their bond, renew romance, apologize for disappointing one another, own their failures and flaws, integrate gender differences into communication, build or recognize separate selves (identities), and inspire the pair-bond to weather the storm.
For partners who have evolved through the previous stages and developed a healthy, well-refined intimate separateness, stability, allowing each separate self to be creative and purposeful in the world in the ways that the self needs to be—through work, parenting, art, craft, sport, relationships, social causes, philanthropy, and the like.
We realize we know how to love now, we know what the heck we are doing! We now codevelop a partnership, attachment, and marriage that “feels right,” “works for us,” “gives us each a lot of what we need.” If by now a divorce has not occurred, a marriage has probably lasted well more than a decade.
Metaphorically, you are Adam and Eve in the garden at the point of eating the apple—you become somewhat ashamed of who you are and/or ashamed of your partner, disillusioned by the loss of perfection. You begin to unconsciously and consciously study your partner for flaws (and so does she or he with you). Because you love this person (and this person loves you), former projections continue and new projections are established, so that bonding can continue, but there is some discomfort in your love now. You may be together three to five years, but the honeymoon is definitely over.