There is a great piece on this subject, just out in the Atlantic, written by sociologist Brad Wilcox: Men and Women Often Expect Different Things When They Move In Together.
As regular followers of our work at the University of Denver know, there can be a lot of misunderstandings about cohabitation stemming from the fact that most couples (really, most!) slide into it without the two partners being all that clear about what it means and where it is going. That is partly why moving in together is such a totally different thing from getting married. While many marriages do not work out like people planned or hoped, at least the meaning of the transition is usually clear with regard to having a future together. This is often not at all true of moving in together.
Wilcox's piece highlights some new findings from a study by sociologists at the Rand Corporation as well as some of the research we and others have done in this area that gets into ways commitment dynamics can be different for men versus women when it comes to cohabiting.
A key line from Wilcox's piece will give you the flavor for what he writes about: "Finally, when she turned 33, Shannon told him she wanted a wedding date, to which he responded that he was not ready for marriage....."
There are a lot of women (and men) who reach a "finally" point, where they realize their partner is not on the same page about a future together when that is what they thought was the whole point. Not only not on the same page, but not even in the same book.
I highly recommend his piece to those of you interested in current trends in relationship development as well as cohabitation. You can read his piece at the link above. Highly recommended!