I want out of the marines?

I signed up for the marines at the end of my sopre year. and i have decided against going for a few reasons. When i signed up i did it with a friend and went with the buddy system. well i had to have surgery for a hernia and i got delayed four days before my ship date. then ten days from my new ship date i get delayed another month so that i can be sent to a specialist in indy. so now i am two months behind from my friend and i have decided i want to go to college and not get into the military. i was wondering if there was any way i can get out of it and how i would go about that.