Not even a question about what to do. If he has violent tendencies in a state where he has no control over himself who is to say he will stop with just hitting you next time. I don't even know you and i can tell you you deserve better. Id say if he can go a year sober and prove it to you give him another chance. As for now i would consider getting some pepper spray and getting the f out of that relationship. Forgive him? That is just completely UNACCEPTABLE. You deserve better and i hope you leave him and he gets help with his disease.