I would counter with how your good looking guy friend and her good looking female friend would make beautiful babies...
Understand this, whether or not a woman says someone is attractive, they sure as heck notice. The less it affects you and you can be logical and measured about it, even joke about it, the more confident you appear and feel. The other night, my gf commented about some actress on tv and asked if I thought she was attractive. I said "sure she is, that's her job." then I said something to the effect of Charlize Theron really was one actress I found particularly attractive and she was near our age. She agreed and said , "I don't like women but I might go gay for her" We ended the convo agreeing that he would be our one exception to the no threeway rule we had.