Why were the Jewish ladies rewarded to get the day of Rosh Hodesh as a special day for themselves, even more than the men?
When the Jewish people sinned with the golden calf, replacing their leader, Moshe Rabbenu, 'a"h, with it, the women refused to participate. The men, in their despair, rushed to bring gold, from which the golden calf was made. The women, however, knowing better, would not give their gold jewelry which was required for the golden calf.
We may wonder, whether their attachment to their jewelry was the real reason. We all know how endearing our jewelry is to us. Nevertheless, when it was time to donate for the building of the Mishkan, the women did just the opposite! They willingly and enthusiastically offered their gold jewelry, even before the men. G-d rewarded the women for their refusal to take part in the sin of the golden calf, which reflected their uncompromising and steadfast faith in G-d. He also rewarded them for their generosity for the building of the Mishkan, which was erected on Rosh Hodesh itself, in the month of Nisan.
We are told (Pirqe Ribbi 'Eli'ezer, chapter 45), that the women were rewarded both in this world and in the world to come. In this world they were given the mini holiday of Rosh Hodesh and in the world to come they would renew themselves like the new moon.
The root of the word Hodesh (month) in Hebrew means "new", or "to renew". Just as the moon renews itself every month, so too the women. Every month, when the wife goes to the Miqweh (Mikveh), her husband waits for her the way we wait for the light of the new moon. She appears to him and he cherishes her as he did on the night of their wedding.