Breaking up is hard, especially when you're not ready. It can take a long time to be ready. It can take a lot of abuse, a lot of giving up hope and a lot of just not caring anymore to be ready. I've been married to an alcoholic 15 years and I'm still here. There was a time when he'd threaten to leave me and I'd burst into tears. I got past that point and he stopped threatening the day I just looked at him blankly when he did.
Living with an alcoholic is living with a monster in the house. The monster has it's own room but there's no lock on the door and it can come after you anytime. You love the house so you keep hoping the monster will stay in it's room and leave you alone. But you have no control over what the monster does. You can tip-toe around so it won't here you, you can try playing monster taming music but nothing you can do will have any effect on the monster. So, you either decide the house is worth having to deal with the monster or you move out. In your case, the monster chased you out before you had a chance to realized the house really wasn't worth it. You hadn't had time to focus on all the other wonderful things outside the house that are waiting for you to learn to enjoy them. It sounds like you're still attached to the monster infested house. Hopefully, you can make yourself focus on happier things. The one time I left my AH was when the monster was rempaging around the house so much that I was in physical danger. I packed our boys up and hit the road. We spent weeks going to fun and interesting places every day, whether I liked it or not. It was hard. I did a lot of reading about alcoholism at that time. I went to a counselor at abused women's service, I got a clear picture of how dangerous my situation had become and I decided I was ready for a divorce. I told AH I wasn't coming back unless he quit drinking. I really thought he'd choose the alcohol over me. I was wrong. He started going to meetings, went on medication and got sober. BUT, guess what... eventually, he stopped going to meetings, then he quit his meds, then he started drinking again. The monster is back.
Aside from thinking out loud... I'm telling you this to A) Ask you to think about what you can do each day to have fun with your son. B) Read all you can to understand what you've been through, that it wasn't your fault and that you had no control over the situation. C) Say, he did you a favor by setting you free, you are better off without him.