@JSK90 Hey, I've been there myself (nearly 10 years this went on for). As your post last night was obviously typed up while in an emotional state, you may have got up this morning with some clarity, or you may still be feeling hurt.
What I want to say is, that regardless of who's right and who's wrong, you need to have a good look at this relationship from a non judgemental and non emotional viewpoint, and ask yourself if this is want you want for yourself. Is it on and off due to the same issues? Do you feel like you are putting in more than you are taking out? Do you feel loved, cherished, and part of his life?
Have an honest opinion with yourself about your self worth. Don't contact him until you are emotionally calm, and while your waiting work out what you want from this relationship, and then sit down with him and tell him calmly. Just remember he may not have the same relationship goals as you and you can't apportion blame if his idea of a relationship is different to yours.
You can't get another human being to change, but you can work toward changing yourself by working on your self worth and having your own life and interests outside of this relationship. If you are constantly telling someone their behaviour to you is unacceptable, but then allowing them back for the same to happen again, then the person has you over a barrel. He knows all he has to do is wait for you to calm down, say a few words he knows you want to hear, and carry on doing what he wants. Please please understand that this isn't a healthy relationship. You may feel like you have control because you are constantly ending it, but believe me, at present he holds all the cards in this.
But I would look into you own actions as well. You may, from a non judgemental observation find you still feel like you were right, but you may equally feel like you over reacted.
Why was it so important to spend yesterday with him and his family? By your account you have only been back together a minimum of 2 months. Is this on and off thing you have going on good for his child? I do get it. I had a childhood of emotional neglect and I really wanted to belong somewhere. But I realised in the end I had to belong to myself. It took a while but once I got that self worth and self compassion even my patchy relationship with my family changed for the better. My 10 year relationship with my partner however ended because I was honest with myself and I realised he wasn't who I wanted him to be. He wasn't going to change. He wasn't even a bad person really, he just had different life and relationship goals to me.
I would advise anyone in the same situation (and I have done several times) to read the book Why Men Love
witches, and it's sequal Why Men Marry
witches. They were written in the 90's so are a bit dated, but they drive home the point succinctly and humouressly that we need to have that self worth for a healthy relationship.
Good luck for your future and I hope you get some clarity soon.