My sense, from talking to my single friends (because I have not been single long term, as an adult), is that single women in particular feel that the church marginalises them. That things in church are geared to married women and mothers, and that you haven't really arrived at maturity until you reach that point. And that your gifts and potential contributions aren't taken seriously. I remember one friend who was working on her PhD, who told me once that it hurt her that if she did finish the doctorate, the church would never acknowledge or celebrate it, but they'd throw kitchen teas and baby showers and acknowledge and celebrate those kinds of milestones.
I've certainly heard loud and clear from single people in church that they feel overlooked in church cultures where everything is geared around families. (And you can see that kind of complaint here in the singles forum, particularly). And in a church culture where the full participation of women is already in question, I think women feel that in a particular way.