In the South Park episode Tom's Rhinoplasty (Season 1, Episode 11), Chef says he struck out with Ms. Ellen because she was a lesbian.
Was this a case of a guy insisting no straight woman would ever refuse him, or was she genuinely only interested in women?
Valorum clearly lists the possibilities, but I disagree on their final conclusion. In my opinion, all signs point to Chef jumping to conclusions due to striking out with her on the date.
If she was actually a lesbian, why would she go on the date in the first place? She could just outright state that she is not into men and avoid the date with Chef altogether.
The only other explanation would be that she went on the date specifically to sabotage the romantic pursuit without letting Chef know that she was a lesbian. But then why would she reveal that she's a lesbian during/after the date as a way to stop a second date? If she was willing to state it, then it does not make sense that she went on the date in the first place.
The remaining explanation would be that she went on the date with an intent to fail it without revealing she's a lesbian, but Chef figured out what she was doing.
While not impossible, it is exceedingly unlikely when you consider the scene in which he reveals this. If Chef is that good at reading the situation, his explanation of what happened would have indicated that he read between the lines. Instead, he makes an off-hand comment about how she's a lesbian and does not give the topic any other oxygen.
This is much more in line with someone using an excuse to avoid a truth they do not want to face, i.e. that Chef can't acknowledge that he might not be able to woo every woman he meets.