I’m sitting in utter shock at my reaction. I’m crying because I don’t know what to do.
If you don't like who you are when you're around someone, remove yourself from them. If you don't like who you're becoming in a relationship, extricate yourself from it and get back to being you.
The same goes for him. He knows he's a nasty drunk so he could choose not to drink and remain a better person. Instead he chooses to be selfish and abusive towards you.
Sleeping pills exist. He's not drinking alcohol to sleep, that's just the excuse he uses to attempt to justify it. Alcohol actually wakes your brain up after a few hours so is not conducive to a goods nights/days sleep. You'll only stay properly asleep if you're passed out unconscious and you don't get like that after only a few drinks.
I guess either he's a functional alcoholic so his addiction isn't at all obvious. Or he's a coward who'd like to split up but is being deliberately cruel so you'll leave him rather than him tell you its over.
I don't believe the theory that drunk people don't know what they're saying. I believe alcohol strips away the veneer of civility we all wear and you see the true character of the person underneath. So if he's a nasty drunk, he's actually nasty sober and is just hiding it very well because he knows it's not socially acceptable. Drunk him has lost all his inhibitions and doesn't care what wider society (or you) thinks, so he lets you see him as he really is.
I'd take him at his word, he's told you to leave. If it's his house and you're not married, go - because you've no rights to stay.
If I was dating someone and they told me they didn't want to live with me any more, I'd consider the relationship over. You're walking on eggshells and don't feel safe, so it's no loss really, is it? Call your friends and family, explain what's happened, pack yours and DC stuff and find somewhere else to stay. Then block his number and move on with your life.