Even their approach to sexuality is traditionally masculine with Jack taking the initiative and making advances on his coworker. Moreover, both Jack and Ennis ascribe to their gender roles such as by marrying a female and bearing children. Jack easily assumes the role of husband and father. One of his most masculine scenes in when he bluntly refuses to run away with Ennis, citing the importance of his role as father. Being a father is a certain expression of masculinity, representing the ability of the man to provide for a family even without taking part in the actual child rearing duties. Both Jack and Ennis seek out and thrive in typically masculine career roles, too. Their ideal work is removed from society, ruggedly independent and decidedly masculine.

Masculinity is therefore a separate issue from male sexuality. The men in the movie are staunchly masculine while being gay -- or at least bisexual -- at the same time. Straight and gay characters are not necessarily portrayed any differently from one another in Brokeback Mountain. The main difference between straight and gay characters is related to homophobia.

Homophobia is a problem affecting both straight and gay men in Brokeback Mountain....

For example, even Ennis is afraid of his feelings for Jack. His initial reaction to Jack is frustration -- with ths major shift in identity the rendezvous represents. Ennis more than Jack understands how deep homophobia is rooted in the rural Wyoming community. He warns Jack about making their relationship public, noting that they could never be accepted as a couple without grave repercussions. Ennis therefore chooses to remain in the closet, and Jack is only slightly more open about his sexual preferences. Homophobia therefore runs deep even within those with genuine feelings towards members of the same sex.
Straight men are like Jack and Ennis: they are cowboys, they have failed relationships, and they just want to express their individuality in rugged Wyoming. Society -- especially the society depicted in Brokeback Mountain -- expects all those born biologically male to act, dress, and communicate in certain ways. Men are supposed to be ruggedly individualistic, independent, and unemotional. Men are supposed to be heads of heterosexual households, allowing their wives to raise the children while they work outside the home. Men are above all supposed to be heterosexual, no matter what their heart might say.