Fifty years after the release of her seminal book, Sex and The Single Girl, in 1962, Helen Gurley Brown has died at age 90. And while many will remember her as the editor-in-chief of Cosmopolitan magazine (1965-1997), I will remember HGB as the first and most significant modern champion of the single woman.

Helen Gurley Brown knew this woman well. When she wrote Sex and the Single Girl she was 40 years old, having wed just three years earlier at age 37 -- very late for the mid-century American woman. But HGB was not going to settle for anything less than what she wanted, calling herself a mouseburger, "someone who worked hard, never surrendered, advanced professionally and married the man of her dreams." She advocated that her single girls do the same.

Back then, and one can argue even still today, a woman was not considered fully grown or mature until she married. HGB could not tolerate that judgment. In an interview with author Roy Newquist in 1967, Gurley Brown explained why she wrote her book: "Nobody was championing [single women]. Volumes had been written about this creature, but they all treated the single girl like a scarlet-fever victim, a misfit, and... you can't really categorize one-third of the female population as misfits."

Helen Gurley Brown was part of my inspiration for what I write about in Huffington Post Women and discuss through my lifestyle brand: Savvy Auntie. At age 38, I set out to champion the nearly 50 percent of American women who are childless, for whatever reason, and show that we are maternal despite not being mothers. Often mistakenly labeled 'selfish,' 'pathetic' or made to feel 'less than' simply because we are childless, I set out to give this segment of modern women the acknowledgment and appreciation they deserve. In the spirit of Helen Gurley Brown, I asked how the woman without children -- every other woman in the United States -- could possibly be less of a woman simply because she is not a mother.

What is remarkable about Sex and the Single Girl was that it was published a year before Betty Friedan's The Feminine Mystique, known today as the feminist manifesto. But while Friedan set out to help make women equal among men, Gurley Brown set out to make single women equal among all women.

In 1982, Gurley Brown published another book entitled: Having It All. The book was aimed at her Cosmopolitan reader; the young, single woman she inspired to have love, success, sex and money, "even if you're starting from nothing." Thirty years later, we are still talking about "having it all," but only in the context of working mothers, excluding single women and childless women from even getting into the conversation. It was Helen Gurley Brown who did not distinguish between married mothers and the single woman when it came to the ability to have it all. It was just a different kind of having it all for each of them. If you were a child of the depression who wasn't expected to amount to much, and you became Helen Gurley Brown, then you knew a kind of "having it all" that all women should aspire to: Living your best life with joy and love, with or without a man. And when the right man comes along, knowing that you've waited for the best love of all.

Helen Gurley Brown and her late husband, David Brown, were married for over 50 years when he died in 2010. They had no children.

Here's to you, Helen Gurley Brown, with love from one of your Single Girls.