Every day I talk to several people who are experiencing serious conflict in their primary relationship. In nearly every case the couple was initially in love, but over time the "in love" feeling slipped away, becoming a distant--often painful--memory.
What happens? Look at the verb associated with romance: We "fall" in love. Falling doesn't take much thought or effort. Just the other day in the woods, I wasn't being careful as I was chopping a tree with an axe, so when I turned around, I caught my foot on a root and fell to the ground. Falling was effortless. Falling can also be enjoyable--skydiving, water slides, and riding a bicycle down a hill come to mind.
In almost all cases, falling in love is like falling down a water slide supported by a raft in the middle of the Pacific Ocean. The fall is great fun, so in the beginning, you don't care that you're out in the middle of the ocean. You also don't notice that the slide is made of a stiff, composite paper material that is beautifully painted. For quite some time, it holds up under the water and the sliding, but as the water soaks into the microscopic separations in the paint--and as it rains and blows from time to time--the paper begins to fall apart.
Finally, the slide dissolves completely, and there you are, sitting on a small raft in the middle of the Pacific. No more sliding. The fun is gone, and you have no idea what to do next.
There's nothing wrong with sliding. It really is fun, and we should be having fun. But before you climb the steps and begin your exhilarating descent, check your location. Be sure the slide is built on firm ground, or, if you're in the Pacific, have a ship standing by.