There is absolutely no point in spending money on a therapist if you don't open up to him. So go ahead and get it over with, ok? I'm glad you are seeing one. Now take the next step. They are trying to figure out what is wrong with you. This guilt that you have is ruining your life.
I've told you before, if you love God, he loves you. Don't sweat anything else. But you need to talk about this. Don't be embarrassed. You think your therapist hasnt heard it all?? They HAVE heard it all, and they are there to help you.