Yea, sissy is not strictly a homosexual derogatory term. It can be used in that context but sissy has meant weak and feeble without having anything to do with sexual orientation for decades. Far as I'm concerned, dude was being presumptuous and interpreted it to mean a homosexual derogatory insult. He could have been referencing the proclivity to tell on someone, which is universally considered to not be a masculine characteristic and has nothing to do with sexuality. A straight man can be a sissy.
There cannot be such an expansive net of offensive words due to extreme sensitivity. You're extremely sensitive? Fine. That's not my problem, and as long as someone didnt use the F-word, then you cannot just presume they were subliminally attacking your sexuality with a word that has meant soft for years. Just like you seem to attenuate a distinction between gender and attraction, masculinity and sexual preference are two different things, too.
And I dont understand this I am attracted to men but not gay concept. I'm accepting of all people's views but that is such a far-fetched perspective for a heterosexual male to understand. It's black and white. You either only like women and don't like men. Or you don't. And there's nothing wrong with liking men but that means you're gay. Why be so defensive over gay insults, yet not proud enough to claim your identity? Seems like you're ashamed of yourself.