June, I am so sorry this happened to you. As a victim of sexual abuse as a child and sexual assault as an adult, it's taken me more than 30 years to talk about it.
Even as a child, you feel guilt that maybe you encouraged the person in some way.

Please work on the feelings of guilt.

YOU are NOT responsible for vile predators' actions.

Do NOT beat yourself up about going to his room because you went because you trusted him. HE betrayed that trust.
He is a sexual predator who got off on your unconscious state. He would have and probably has done it to more than one girl. He would have done it if he could get away with it in church. His room was just convenient.

Rapists come in all shapes and sizes and often it's the good-looking ones who are worse because they believe their looks or position in life entitles them to take without permission.

You are strong and beautiful and writing this may help others also get rid of the guilt.

Thank you for writing this.

Good luck with your journey going forward. 🙏🏾