If I were to aver homosexuality a choice, I'm sure I would be attacked. Yet bisexuality claims that very thing. The basic 'born that way' argument would be destroyed if sexuality was not fixed but choice.
If Jane can just as easily have sex with Ann as with Al, gaining just as much pleasure, then homosexuality would not be 'fixed'.
As Wolf mentioned with lesbians...question...are they lesbians? Was their relationship with another woman more an escape from bad experiences with men, and then a lack of sexual fulfillment sent them back?
As there is no 'gay gene' as the question of 'born that way' contra 'choice' is still debated.
In the present case it seems to me that the husband has been using his marriage as a 'beard'.
Simply put, sexual relations with a woman do not fulfill him, he is expressing his attraction for other men, which one assumes is not a recent trait.
A lot of people, male and female, did what society 'wanted' them to do. They got married and had children.
Now that they have fulfilled their 'payment' to society they no longer can suppress who they are.
Many homosexuals, as 'motherof..' mentioned above have
fulfilled this societal demand.
There is still debate about bisexuality. Put it simply,
a thirty year old might be experimenting, might be unsure, and go through this 'phase' and then elect to be one or the other.
The question here though is that a woman married a man she thought was straight. She lived with him, they had children, and now suddenly she realises she doesn't know him.
It is not just the sexuality which is the focus. For example, a chap married. After ten years, by accident he learned that his wife had been a prostitute.
In another case, it was only on his death that a wife learned her husband had been married to another woman when he married her.
It is the realisation that you don't know this person.