I think it's worth noting that fat guys are just as likely as thin guys to insult fat girls.
Also, guys get a lot of shit for looking/doing anything/being anything too "female-like". So if you happen to have a more feminine frame, you're screwed. And of course, they associate feminine men with homosexuality.
So, in short, men view "womenly" men as "pussies, faggots, pansies", and men view "manly" women as "pretenders, rabid feminists, misandrists, hypocrites."