As an Christian turned Atheist/Deist, I can only tell you my views on religion and the choices we all should make. In Judaism when a child becomes mature in the eyes of the Synagogue, they make a choice on whether to embrace Judaism as an adult, and I believe that this should be a part of all religion. In the end it is your life and your decision to make. If you no longer believe in Muslim ideals, then reevaluate whether you agree with any part of the Muslim faith. If you find yourself unsure or doubtful, do more research and think on it for a while. When you're ready make a choice on whether to leave the faith or not, taking into account the opinion your family will have of your afterwards and whether they will accept this choice or disown you leaving you vulnerable. This makes it not completely your choice but this is the cruel world we live in. This is why when I have children they shall not be raised religiously (though they might be christened to appease my relatives) and be able to form their own opinions on life and the world. If they turn out to accept Islam, Judaism, Buddhism, Sikhism, Catholicism, Protestantism, Buddhism or even Scientology, they shall have my blessing.