In popular culture, particularly in media such as television (think sitcoms) the strong confident woman is often portrayed as a bit of a ball breaker, as being emasculating of her man, and really something of a bitch.
Conversely the man she is with is seen as being henpecked, weak willed or as having no particular gumption. What is also portrayed in popular imagery is the man then coming into his own and breaking free from the emasculating fetters that the female placed upon him.
However is this really true? Does male emasculation have to be the casualty of female strength? In short is it always threatening for a man to be with a strong, self possessed and independent woman? Particularly a woman who may be better educated than him or who may be making more money?
Well the answer would be yes and no. It is true that traditional family roles place the woman in charge of hearth and home whereas the man is supposed to be the provider and the defender.
So it may well be that the strong minded woman who can fend for herself and her family, who has opinions and is able to defend them; who is a problem solver in her own right may be perceived as overbearing by the older generation. This is understandable and is almost expected in the historical context.
Also for men who were brought up with very traditional values this may still be true. Men with misogynistic tendencies or those who were brought up with values that viewed strong women negatively would also likely have a problem with strong women.
But increasingly relationships are not viewed as being the union of one dominant and one submissive member. As gender roles change and more and more women dare to make advances in the corporate world and as more men feel no shame in assuming the role of a homemaker or at least part homemaker and equal contributor at home, this power dynamics change.
Society is far more accepting of women who are successful and men who are supportive of that success. Society no longer scorns such unions; and no longer expects the man to be assertive in order to be a man. The traditional accepted norms of male and female behavior are changing, becoming more flexible, less rigid and more all embracing.
Men are not under as much pressure to be manly (read assertive) and similarly women do not have to be helpless in order to appear feminine. So as relationships mature and evolve into partnerships based on equality, men and women find there is less pressure to conform to a traditional ideal and hence men find they are able to be comfortable in their manliness, even when there is a strong woman around.