Men and women are not naturally compatible

But what is the new work of marriage like? Do men and women actually want the same things? If not, will they be happy to compromise on what they want? "Sometimes I wonder if men and women really suit each other," said Katharine Hepburn. "Perhaps they should live next door and just visit now and then."

-- excerpted from: The gap between men and women

by  Jane Sullivanreports.

Pressures on straights to be heterosexual

"Compulsory heterosexuality isn’t just about compelling people not to be gay. It’s about the social pressures to perform heterosexuality that are put on everyone, regardless of sexual orientation. Even if you’re straight, you can be subject to this pressure if your straightness doesn’t conform to the get married/have kids/participate in the rituals of American heterosexuality."

-- Amanda Marcotte in Education, Boggles the Mind, Signs of the Non-Apocalypse, Feminism

...

Reproduction no reason to promote heterosexuality

"Food tastes good. It is pleasurable to eat foods one likes. That doesn't necessarily entail being a glutton, just because food is pleasurable to eat.
Food is also far more necessary to sustaining life than sex is. Sex may facilitate procreation, but procreation by itself doesn't put food on the table, or fire in the hearth, or clothing on the body. 
By that same token, sex being pleasurable and the fact that male-female coupling leads to conception does not mean that one should do it endlessly. "

--  Giambatista, an internet discussion poster

"Again I must ask, why does "Be fruitful and multiply" survive as a commandment while most other directives from the Old Testament either get thrown into the trash, or only receive passing mention from most professing Christians?"

--  Giambatista again

Presuming 'heterosexuality' to be majority and male to male desire to be minority

The nature of the problem to be discussed can be indicated by asking whether homosexuality and heterosexuality are biological categories that divide the world into a majority and a minority that can be found in all times and places. To such a question most western people today would reply yes. And while they would probably wonder why a minority should be homosexual, they would simply accept without question that most people are heterosexual. Since the 1970s, however, the work of some historians and sociologists has radically challenged these presumptions.

-- Randolph Trumbach, in the article
The third gender in twentieth-century America
published in:
Journal of Social History, Winter, 1996 by Randolph Trumbach

Greek men and their boy lovers

the moment of the boy’s first stubble is so often conceived in poetry as a time of
great loss, when a beloved boy is suddenly too old to be respectably the object
of a man’s passion, and must be allowed to find a boyfriend of his own.

-- Gregory Woods
A History of Gay Literature: The Male Tradition (New Haven and London,
Yale University Press, 1998), 30.

Gay-straight divide 'an absurdity,' Queer as Folk star says

"I'm really not one of those guys who makes gay jokes, because I don't think those jokes are about homosexuality. I think they're about the feminine. Men have difficulty dealing with the feminine. Dealing with anything that is receptive or passive scares them. And the idea that a dude would be receptive or passive scares the crap out of them."

"Playing the part gave him new insight into the ridiculous segregation between straight and gay men. It  left me feeling like I was standing on a bridge looking at two warring parties and going: 'You know you're both insane, right?'"

-- Hal Sparks, the straight actor who played the part of a married gay man in the television serial "Queer as folk".