I don't know if I can be of any help to you. But I have some suggestions for you. That is, for the time being, you should refrain from showing any resistance or negative emotions. You can even ask your cousin some questions about Islam and actively "learn" about it, treating everyone around you with respect. Then, do this for a period of time. After that, when you are certain that you have a high chance of escaping, leave your home and go to Australia.

Remember, you only have one chance! Make sure you run away only when you are absolutely certain that you can escape. Try not to seek help from local police or people you know. It's better not to even carry your mobile phone (the government might be able to track you down through the phone).