Romantic and passionate love can fade over time and mature into a committed love.

Couples can rekindle the sparks of early courtship simply by doing something novel together. Studies show that partners who regularly share new experiences report greater boosts in marital happiness.

Committed couples do have more sex than everyone else. But Americans who are not having that much physical intimacy are just as happy as their more active counterparts.

Sexual frequency declines 3.2 percent a year after the age of 25. But the good news is that what married couples lack in quantity they make up for in quality. *

Ways you can protect your relationship:

• Avoid opportunity. Avoid situations that could lead to bad decisions, such as late nights with colleagues.
• Plan ahead for temptation. Remind yourself of steps you will take to avoid temptation and protect your relationship.
• Picture your beloved. Focus on loving thoughts and the joy of your family.
• Keep your relationship interesting.

Learn to fight constructively. The aim is to leave you feeling better about your partner.

• Identify the complaint, not the criticism.
• Avoid "you" phrases. '"You never" and "You always" followed by criticism.
• Consider your pronouns. Starting your sentence with "I" or "We" will help identify problems, rather than blaming.
• Body language. No eye-rolling, folded arms, or crossed legs. Look at your partner when you speak.
• Learn to de-escalate. Useful phrases include "What if we...", "I hear what you're saying..."

Fights about money are really about a couple's values and shared goals and seldom about finances itself.

• Be honest about all your spending.
• Maintain some financial independence. Both sides can have their discretionary pot of money to spend on whatever they want.
• Invest in the relationship. When you do have money to spend, spend it on the relationship.

The top three predictors of a happy marriage among parents are:

• Sexual intimacy
• Commitment to the relationship.
• Generosity. It's about sharing, caring and kind gestures you make toward your partner every day.

• Stay generous toward your partner. Continue to express your affection. Do small things for your partner like bringing them coffee.
• Personal growth. If your partner is helping you become a better person, you become happier and more content.
• Be decisive. Intentionally define your relationship.
• Invest in relationships with friends and family.
• To strengthen a marriage, consider asking less. That means leaning on others for emotional support from time to time.
• Watch a love story. A movie about relationships can help couples work out problems in the real world.