Firstly, I would like to say congratulations on being smart enough and strong enough to call into question the JW religion at such a young age. Very impressive.
Please understand that it is very difficult for anyone to give you advice due to your age and not knowing in detail your circumstances.
From what you have said so far, it seems that you are doing things correctly by learning about the alternative perspectives the Jehovah's Witnesses don't teach you. The more you learn the easier it will be for you to see through the illusion of it all.
If your aunt is your legal guardian, it might be advisable not to confront her about your doubts right now. In fact, you might want to keep your doubts from everybody as it could cause them to work harder to get you to conform.
Coming off the ministry school might be a good idea. You could always make the excuse that you find it a little intimidating. That was the excuse I used when I was your age and it worked fine.
You are going to need lots of support to help you through this, so keep posting on here as much as you can. I'm sure people here will be delighted to be of assistance.
It is also very important that you make a friends network outside of the religion. This might prove to be difficult as it is so discouraged by the JWs.
I'm so sorry that you are having to face this at your age, but I hope you can realise how well you are doing to be able to see through this religion at the tender age of 13.
JW Facts is a great site for the information you are looking for. Just take your time and don't rush anything.
I look forward to reading your future posts and it would be great to hear about what you learn from your research.
Please keep us posted on your progress.