Relationships begin with infatuation. A crush is often mistaken for love because it is so powerful and indescribable, even though it is fleeting in the end. Romantic love leaves an imprint on the heart and psyche that is hard to shake.

When love matures and the romantic sentiment fades over the years of managing kids, chores, jobs, money, family dynamics and other commitments, the memory of that imprint can cause misery as couples feel loss. This is a pivotal point when marriage begins to unravel...