The other day I was in the car with a good friend of mine when she referenced staying in her job (that she doesn't love) because she "makes good money." Curious as to whether we agreed on what that means, I asked her rather casually, "So how much do you make?"

She got very quiet, then looked over as if checking to see whether I actually expected her to answer.

"You don't have to tell me if you don't want to," I said, realizing she was uncomfortable.

"No, no," she said, "I mean I guess we're close enough - I can share that with you."

When it comes to women, money is the last truly taboo subject. It's significantly easier to talk to another woman about sex than to ask her how much she makes.

In fact, research by Fidelity Investments showed that 80 percent of women say they purposefully shy away from discussing money with family and friends.

Consider that for a moment: 4 out of 5 women don't talk about money.

This is a mistake of massive proportions. Why? Because it's costing us:

  • Women's earnings average $0.79 for every $1.00 earned by men, which equates to a lifetime loss of over $300,000
  • The gap is even worse at the top: In the top 1 percent of earners, women are paid $0.46 on the dollar
  • According to a new report by the National Partnership for Women & Families, this wage gap is responsible for women in the U.S. losing out on $500 billion per year

Most women and men I know want to see this change. I don't know a single person that thinks, "Yeah, I think it's completely reasonable that women make half a trillion dollars less than men for doing the same work."

Yet most of us are at a loss in terms of how to actually change it.

I'd argue that it starts with shifting the culture around women and money - and that this starts with us talking about it with one another, openly and often.

There are all kinds of reasons that, as women, we hesitate when it comes to talking about money. We might think we make too much compared to the other person and don't want to "make them feel bad." We might think we make too little, and we're quietly ashamed about it. We may have been raised to never talk about money "in polite company" (whatever that means) or to avoid putting someone on the spot by asking them about such a "personal" matter.

Whatever the reason, we've got to get over it. Period.

We'll never get rid of the wage gap if we don't get rid of the stigma.

Fortunately, we can do that. One woman, one conversation, one group discussion at a time, we can shift the culture.

It starts here: Do you know how much your three closest women friends make? If not, open up a dialogue about it.

Rather than saying, "If you don't mind my asking, how much do you make at your job?" consider introducing the topic by saying, "Hey, I'm working on being more transparent and empowered about money. Can we have an honest discussion about it?"

Talk about money, and don't stop at how much your friends make in terms of salary. Ask (and answer) questions about how the women you know talk about raises. Ask (and answer) about credit card debt, investments, and retirement accounts. Practice sharing your own financial situation over and over, and listening to others.

We need to make this a priority - as in more important than other things (like seeming polite, not making someone else uncomfortable or worrying about how we'll look). Because silence leads to shame, shame leads to paralysis, and paralysis apparently leads to a $500 billion wage gap.

I consider myself an empowered and educated woman, and view my friend in much the same way. Yet it was still a "thing" for me to ask, and it was clearly a "thing" for her to answer. She did eventually tell me, but it wasn't comfortable.

My main takeaway was this: If we're going to get over this, we've got to accept that it's going to be uncomfortable ... and do it anyway.

All that talk about the value of getting out of your comfort zone?

Time to put your money where your mouth is.

"I've been rich and I've been poor. It's better to be rich."--Gertrude Stein