I'd never heard the word used in such a context prior to reading this thread. Seems rather odd though, considering the individual chooses who they find attractive and beauty is in the eye of the beholder, as it were. I don't see how anyone is trapped into anything. The only trap I can see is that which everyone comes into contact with on a regular basis: that of assumption. And that trap is always laid by the individual, not the object of their libido.
I find it difficult to empathise with the need to blame someone else for one's own thoughts and actions, and I see the word used in this context as simply a way to avoid examining or taking responsibility for such thoughts and actions, stemming from an innately percieved question to one's own heterosexuality.