I don’t believe in the static self, the idea that who you are is determined at birth. In fairness, most people also don’t believe in the static self up until it comes to identity.
For me, I truly believe that my identity is influenced by how I was raised. My parents (and my father in particular) raised me as their first son and their first daughter. While I was expected to be feminine outside of the home, inside my house was different story.
All the things expected of boys, of men, were placed on my shoulders due to being the eldest sibling. My dad would regularly confuse me for his son, accidentally use he/him pronouns for me, and overall expect me to uphold the masculine ideals he kept for himself.
But I still wasn't given access to masculinity. Though I had internalized the very masculine standards I was held to (especially the toxic masculine ones like not crying, leadership, emotional detachment —those things), the outside world refused to see me as masculine.
Before I ever thought of myself as bigender, I saw myself as a masculine woman first. Then, as it became clear that no one else would take me seriously as a masculine woman, I considered gender apathy. I thought that because I didn't really see myself as feminine. It might be that I wasn't very attached to being a woman. I knew I could perform femininity and, yeah, enjoy it too but, at my core, it wasn't how I saw myself.
Outside of the romantic implications of marriage, I also struggled alot with the idea that I would be expected to take a submissive role in the relationship which (in my family) was synonymous with the idea that I'd have to find a man that "brings out my femininity." Even small things like doing DIY repairs was something my parents felt I should stop doing. After all, I'd have a man to do that for me (or call someone if he couldn't).
I know I've joking talked about how little I want that but I cannot capture the actual distaste and terror that runs through me at imagining that for myself. A future me that looks like that is a future me that's decided that slowly dying in the closet was somehow worth it.
It is only when I am seen and acknowledged as a masculine woman that I am most myself.