Boyfriend turned out to be psycho, how do I move on?

ok recently I'd been dating this guy. I fell in love with him, don't ask me how. We grew close really fast. He was really good to me for the first month he knew me for the most part, but I noticed he didnt like it when I stood up for myself at all. I told him I had a lot of feelings for him, and he was still deciding if he wanted a relationship with me. Sooner or later, he started trying to break me down telling me that I needed anti depressants because of the way I would react when he kept being wishy washy and jerky with me. Oh this guy has a child too, so I'm not sure how many girls my age would be interested in him. Anyways, I'm told hes had a really bad past. So one time last week I get a text from him saying I need to move on with things and hes met someone else. Hes seeing this new girl now. My friend works with him, so he sees her with him and apparantly shes this really sort of ugly gles wearing curly haired church girl. I figure he picked her up cuz she would fall for his tricks. He was also doing this behind my back for a month. shes older like 31..break her down before he starts to abuse her too. I just don't get any of this. I feel SICK I dated someone like that so beneath me, and I have to keep hearing about it from my friend cuz she works with him. It just became clear to me..that he must have never cared for me at all if he was able to move on so quickly with things...I feel like these types of people maybe never really like anyone, and just use them for their own use. What am I supposed to do, how do I get over this?