As of right now I'm questioning if god even exsist.
That's just reality. There is zero proof the supernatural world exists, so this "certainty" you had before you woke up was fake. Accepting that we don't know everything about the universe can be freeing and restore the sense of curiosity and wonder the cult replaces with bans on independent thinking.
I now realized that I got married for the wrong reasons..
That sucks. Now your opportunity is to explore your relationship as it now is and what prospects it holds for both of you.
You mentioned you started studying in "Nov/13". Do you mean November 2013? So it's been less than a year that you've been studying and married?
So much of life is ahead of you, and even if you were partly affected by the cult before last year, you still avoided so much by not being directly involved all your life.
I'm lost and I don't know how I'm going to break to my friends that I'm not going anymore..
You actually don't have to tell them. They'll notice you're gone, and the love bombing will begin. If they ask, you are free to not respond or say you don't want to talk about it. If you choose to respond, that's your choice--no one is forcing you.
You mentioned they bought you dresses. That is a new one on me. I guess they've taken love bombing and mothering to a whole new level. Seems weird.