That’s awful. Scary. So sorry to hear it

I suspect he is a bully even without sexual issue. Are you afraid of him? Otherwise I am surprised you didn’t react when you caught him doing it. You wake up and are afraid to say something? You need to be “prepared” to talk to him? All signs that you are being bullied and abused in this marriage.

Get your affairs in order, see a lawyer and file for divorce ASAP and until it’s official don’t share a bed.