I wouldnt consider changing my sexual attraction mastering my mind. Its the decision of my body's chemical processes what sex im attracted to, not my conscious thought.
Not wanting to change your sexual attraction is your choice then, right?
I would not want you to change that which you do not want to change.
Sex attraction is all chemical? Nah.... Sure there's a part that's chemical but that's not all of it.
My bet is a girl or a guy goes down on you while your asleep your bodies not gonna care.