Women play a more major part in this, as I see it. Men are "supposed to" spread their genes around, and are more prone to casual sex. Not that it makes it right, but it happens more often.
Women have always been the more civilizing influence on the family structure. We have the power to say "no" under most circumstances (in the West, at least), the power to attract the most deserving male, the power to keep the spouse at least involved in the family structure...using sex and intimacy, of course.
We have the power to keep our legs closed. Feminazis and nihilists have trained our young women to pleasure themselves first, be "like men" (not meant as an insult) in order to gain power in society, and to throw away the civilizing influence of femininity and womanhood. Instead, we are told to substitute permissiveness for permission on the grounds that "it's not fair" that men can do it and we can't. Then we whine that we aren't taken seriously, that we get the raw end of the stick when a man uses us, and we demand that we be viewed as women, dammit.
Why? Aren't we now just men with boobs?
Yes, but the fact is that some women want babies without husbands. Men have got to realize this and see that their concepts of manhood are being used against them. That they choose not to see this does not make them victims of forced-fatherhood when baby results.