Just to clear things up I do not have multiple personalities, when I say Charni I mean when I am feeling female and James is when I am feeling male (I am genderfluid and I don't like being called James when I am Charni). Basically when I am female/Charni, I want a female body. The breasts, the hormones and the genatils. But when I am James I do not want that, I want to keep my male body. What can I do?
I think if possible you should try to seek out therapy. Getting to talk to a professional in person would likely go a long way to making you feel more comfortable, and likely even give you some ideas as to what kind of lifestyle could make you most happy as genderfluid.
Not wanting to discuss this with your parents is only natural. Is there someone at your school you would feel comfortable going to for help? Perhaps a guidance counselor?
Can you tell your parents you're under a lot of stress, and working through some stuff, and want to talk to a therapist about it? You wouldn't have to tell them what the issue is. Of course, it would probably be best to see a therapist who has background with gender issues, but this might at least get things rolling.
They would force me to tell them, then they would go on and on about how stupid I am and how Charni isn't real.
They cannot force you to tell them anything (I'm thinking waterboarding, fingernail pulling, Chinese water torture, etc. ...I could be wrong, but I don't think they'll go there), and I do NOT recommend you tell them. But parents should want you to get support for trouble you're having, and the whole point of therapy is to be able to talk about things you need professional help with, or don't want to talk to others about. It sounds like maybe they don't understand that...but you might consider whether you can help them to understand that...WITHOUT telling them what the issue is. Oh, James/Charni, I wish you luck with this...but it sounds like you'd benefit from getting help.
James/Charni do you know what the legal age of free consent is in Australia? I know here in Canada you can go to a GP without parental consent at the age of 16 and a GP should be able to refer you to someone who can help you sort this all out. As an ocd sufferer DON'T do this alone unless you have too. Getting help from an outsider helps you immensely and will even help you grow as a person. A good councilor will help you and enlighten you in ways you never imagined.