You're not dumb. You found this place and reached out for help didn't you?
I know it's hard, but trust me, after watching my father nearly strangle my mother to death, I can say with all honesty and concern that if he had already pulled a gun on you he's not just going to be okay...and neither are you. While you are away from him, take time to educate yourself. Also, think of ways to protect yourself. There are many resources.
Let him figure out if he wants help, but please don't put yourself in his destructive path. I know I am pleading here, but from the outside looking in and I can't see one reason why you should put yourself through this.
Keep reading and posting. We're all here for you!