HELP PLEASE❗️❗️❗️My ex was horrible to me when he was drunk last night

Last night I went out for a friends birthday, and I saw my ex boyfriend. He broke up with me a month ago on our on year anniversary. Last Saturday I stayed at his after a night out and we had such a nice time we talked and laughed and it was like how we were before. But last night he completely switched, we were both drinking and he treated me like shit. I did nothing wrong, I tried to speak to him several times and be nice to him, he shoved me off of him. He was rude and cold and absolutely horrible to me. I didn’t even recognise him, I have never felt so worthless in my life. He told me to fuck off repeatedly, and just kept being so horrible to me. I know we were both drunk, but I haven’t done anything wrong. I don’t know what to do, I am completely heartbroken and I hate him for the way he has turned out and treated me. I feel completely lost. Someone please help me.