How angry and/or hurt will they be if you apply against their wishes?
How much more upset will you be if you are accepted and they refuse to let you attend? Will you be even more upset than you are now, knowing that you were accepted but still unable to attend?
TheDidactic states that your are an adult and able to make your own decisions. HOWEVER, being an adult would mean figuring out how to pay for this school without help from your parents. They do not owe you an education, and if it is their money, they have the ultimate say in what schools they are willing to pay for. Their opinion matters. A lot.