Is it just me, or...?

Now, I identify myself as biual and approximately 80% of my friends are gay or . Two of my gay female friends are in relationships with women with whom have never been in a previous relationship with a woman and yet now claim to be s. Now, both women claim that their current partners are the only women who they are and have ever been attracted to. Is it just me who is frustrated by their certainty of supposedly being a ? Are they being foolish? Could they be a ? Are they biual? What's your opinion?