I literally had a friend, that wanted to suck my schlong. But not because he was gay, but because he just loved dicks and hated vaginas. He swore he was straight, but women just repelled him sexually. Men too, but dicks were awesome, and visually pleasing and...
When I tried to convince him that I'm flattered but just don't like wieners at all, he was pissed at me for implying that he would be gay. Which he clearly was not. According to him. He then didn't want to my friend anymore, because being told to be gay would be super mean.
Well....the cognitive dissonance in some people is very colorful and vivid.