I think there is a population of men who have found themselves in relationships where the roles they had expected themselves to fill are not realized because the female partner is behaving inconsiderately, and the male partner does not feel entitled to assert himself. The latter in my opinion is the fault of misinterpreted feminism, which to a large extent has focused on emasculating men as a means to promote women's rights.
Men are really pretty good at coping with this situation. We can withdraw from relationships where our partners appear to have no interest in the masculine qualities we were expecting to bring to the table. So we focus on our jobs, go to our ball games and our dens and we spend time with our friends instead. Lots of men live very well like this for lifetimes.
The women are really the victims in this situation. Women can handle a lot but do not cope well with lack of love and attention. So they find themselves frustrated, depressed and in a state that is generally known as “life ache” in my part of the world. The condition often translates to physical illness if it continues over many years.
Some women are smart enough to analyze their situation and understand what they have been missing. A few of these are brave enough to speak with their husbands about it, and a subset of these will get a positive response from a husband, who will understand that he is now being offered what he was missing in the first place.