1. Your partner assumes you no longer care Yes, life gets busy. But rightly or wrongly, your partner may come to feel that your everyday inattention means that he or she no longer matters to you. Whether you've just given birth to your second child, or your demanding job has you traveling more often than you would like, your marriage is vulnerable when your attention is elsewhere. You see, when you were "in love", you had this inner sense that you'd always be enough for your beloved, just as you are. As the initial love hormones diminish, small mindful gestures of attention and affection make a huge difference, provided they matter to your spouse. Make it clear to each other that, "No matter what, when you need my attention, I'll clear out time for you." In doing so, you make your partner less tempted to cheat. Granted, maybe you won't have time the split second one of you gets home, but take your partner's request seriously.

Whether it's a long distance call or after the kids go to bed, put on your best listening ears and be there for your partner (and don't problem solve until asked ... just listen!).

1. Opportunity leads to promiscuity

According to one recent study, "More than one-third (36 percent) of men and 13 percent of women said that they gave in to temptation on a business trip."

You're alone with no one to talk to, plus you're enjoying a few drinks, and in that situation, inhibitions plummet. Highly committed couples know this and make it a point to touch base around the world by phone, even if it's the middle of the night or you must interrupt your business dinner.

Want to know a set up for an erotic extramarital encounter? Complete a challenging project or deal with a good looking team member of the opposite sex in another part of the world.

If you want to safeguard your marriage, make fidelity a much talked about big deal. Explain what it would mean to you if your partner betrayed you. Let that be on your partner's mind because you have