Hey Marlie
The way I see it, whichever gender someone is attracted to is their own busieness. It's not an illness or a choice, It's simply the way they are. ( e.g. I am straight for the same reasons you are bisexual ---whatever the resons are)
You have nothing to be ashamed of. The bigotry and hatred shown by others is a sign of an immature society.
Please stop hateing yourself and wasting your life, make peace with yourself and enjoy your life !!