Money and sex are the two things responsible for driving a toxic wedge in most relationships. Here is something I could never understand. How does a woman, who has been conditioned her entire life to believe that the man is the main breadwinner, change gears and take on a new role? A role that requires her to bring home most of the bacon.

Like any great social change, “The Miranda Complex” does not happen without victims. Remember Miranda in Sex and the City? She was the lawyer dating the bartender, whose income and social skills were not up to par with hers. Today, many women are finding out firsthand that a relationship between a successful woman and a man with less income is very complicated. It raises many different issues that, over time, could end up hurting both partners and breaking up the relationship.

Today, two-thirds of women over the age of 40 earn more than their men, so it’s not hard to understand why so much trouble is brewing in paradise.

“The woman making more money than the man creates a problem,” says psychiatrist and relationship expert Dr. Gail Saltz. Just as women have been conditioned to be cared for, men see themselves as providers. When that role is taken from them, their male psyche is severely bruised.

“Our respect for our partner is based on whether they are living up to their gender expectations,” says Professor Janet Reibstein, a psychologist and author of The Best Kept Secret: Men & Women’s Stories of Lasting Love. “Higher-income women struggle to respect their low-paid men because social prejudice says a man should keep his wife.

“Women want to be in charge of their lives and careers, but they also have a conflicting need to know that their man will take care of them if necessary. When that doesn’t happen, a woman’s sense of femininity and a man’s sense of masculinity is often threatened”.

Whether they admit it or not, women will resent their man spending their hard-earned money on “men’s toys” that they couldn’t afford without his financial help. Do the most successful men secretly resent when their wives are spending their hard-earned money? I don’t know. Maybe they will, but don’t say anything because it’s always been their job to be the provider.

When low-income men feel slighted and high-income women resentful, there is another part of the relationship that goes downhill very quickly. Your sex life. It is quite common for women with high incomes to abstain from sex when they are not getting what they think is theirs. It doesn’t take long for her to figure out the “one with the golden rules” way of doing business.

A 2006 University of Virginia study of 5,000 women found that they were happiest when their husbands contributed 68 percent or more of the household’s income. “Married women have happier marriages when their husband is a good provider,” says Professor Steven Nock, co-author of the study.

Until both sexes learn to unplug the wiring that defines gender roles, it will be difficult to find the balance that gives both people what they truly seek.