Psychologists, sex therapists, and marriage experts have tried to answer the question of why two people who passionately loved each other at one time will decide to split up down the road.

What’s going on that makes former lovers and friends decide that they will be better off alone?

We’re getting much closer to an answer now, thanks to longitudinal studies of thousands of couples. (Our tax dollars being put to good work.)

Certain factors, including ethnic background and financial and social status are beyond a couple’s control. Other factors, however, are very much within your control.

One study used data from 4,500 respondents who participated in the Florida Family Formation Survey. It found that no matter what a person’s income level, a common problem was wanting more affection from one’s partner.

If you are someone who is comfortable with affection, but you know that you are not expressing the affection you feel for your partner in your day to day life, make a promise to yourself that you will begin — today — to give your partner an affectionate pat, squeeze, or kiss every day.

If you have to, program your PDAs (personal displays of affection) into your PDA (personal digital assistant).

And remember, it takes 28 days to form a new habit. You'll notice a warming of your relationship in about that much time.