Relationships go in cycles. Some periods remind you of that "first time we met" phase when you are excitedly discovering one another. Other times you feel removed, alone, and confused by the person living next to you.
One of the most powerful lessons I've learned in the 7 years of our marriage has been the power of decisions. This was reinforced when we watched Fireproof. (It's a movie I recommend to anyone, especially those about to start a life together, regardless of your religious faith.)
On day two of the love challenge, the man is told that love is not about the heart but rather the determination to do nice things for your loved one without an expectation of a return.
One of the most damaging myths of marriage is that once started in love, everything will remain hunky-dorry. I've often joked about writing a sequel to Cinderella entitled "But the Story Said 'Happily Ever After!'"
You've got to decide, every day, to do something for your loved one. It's about her or his needs, not your own. By listening and serving, you are loving. All this takes is a decision.
This aspect of a relationship is especially important when you have children, a point brought home perfectly by Dr. Bill Doherty. (And, I do agree with Dr. Doherty: If it's an abusive situation, get out.)