Its because society attributes double standards to most things.
Its absolutely terrible for a woman to get raped, but for men, they are considered "lucky" or "faggots".
According to gender stereotypes, men always want sex. If they dont want sex, they must be gay. This stereotype is heavily perpetuated by women...who frequently accuse of men of being gay if their advances aren't recipocrated. To imagine how ridiculous this is, imagine if a guy asked you out, was turned down, and then accused you of being a lesbian.
I have religious friends who were accused of being gay by women who didn't want to wait to wait till marriage, or were pissed that the guy wasn't making a move on them. Or they convinced themselves that the guy was cheating on them with another woman, and therefore wasn't interested in them sexually.
Ironically in olden times, rape wasnt considered a big deal because "oh well you are just a woman, you probably liked it anyway".
If a man got raped by another man, he is accused of being a faggot because he wasnt strong enough to defend himself. Gender stereotypes again, if a man cant fight, he is a "faggot" and "not a real man". Meanwhile there is no expectation for a woman to defend herself, so if a woman is attacked, she immediately receives sympathy because it wasnt possible for her to defend herself anyway, nevermind that they could have taken martial arts or purchased a self defense tool.
But its considered completely unacceptable for a man to not fight his attacker/s off.