Please don't beat yourself up for caring, for hoping that this guy could be different. I was with my partner for 10 years,7 of those were pure bliss. It was a honeymoon period for the whole time.
Then he saturating his hands on me. It was a text book progression. Started with getting right up in my face, by the third year he broke my jaw, shattered All my teeth, tried to break my neck etc...
I hung on because I had 7 years of pure happiness and couldn't let it go.

It took him 3years to make that progression.Your man is over halfway there in a matter of days.

Your feelings are totally valid, and obviously there is something in him that made it worth giving it a try.
That person was worth caring for, however the person he is when he drinks is not safe, and you can do nothing to save him.
Please take very serious precautions before you tell him, abusers do not as a rule take rejection well. And distance can prove no object to a drunk when feels he is entitled.

Please have a number of a shelter to hand, perhaps call them in advance to explain your situation.
Be careful. I very much hope it turns out to be amicable, despite it all.
Take care.