The first thing you need to do is make friends with your dad again. I'm sure if you sit down with him and talk things over, you'll both be able to work thungs out. You need to let him know that you're willing to listen to him, but that the final decision is yours. This is not about feeling guilty because you don't want to let him down. This is about doing what you think is right for you. I'm sure if he can see that you are serious, he will stand by you and offer you the support you need. And remember, if one day you decide to do things differently, there's nothing stopping you from doing so.