She said "Well gay guys are attractive."
So, by that logic, only ugly guys are straight, and good luck for them, therefore, no babies to preserve our species. Nice.
Actually, she didn't say "only" gay guys are attractive.
She simply means that gay men in general are attractive as a rule.
However, for what she said first said to be true, what you said must be true.
Because how she said it would lead to this:
First Truth: Gay men are attractive.
Second Truth: Reppy is a gay man.
Conclusion: Reppy is attractive.
But what you said would lead to this.
First Truth: Attractive men are gay.
Second Truth: Reppy is an attractive man.
Conclusion: Reppy is gay.
However, because Reppy is not gay, the first is untrue and because there are attractive straight men, the second is untrue. ;P
This leads all claims to be false and makes the argument that reppy is gay fall to pieces. ^^