Newly Single mom

I am 23 years old. I have a 2 year old beautiful baby girl and a handsome 1 year old son. My ex fiancé and I have been on and off since I was 15 . 2 days ago he left and didn’t leave any sort of financial help for the future for our children knowing both of them are in diapers. He packed his stuff and left and was randomly accusing me of cheating. All I ever do is work, come home , take care of my kids, and sleep. He would try to tell me how to dress or judge me if I wore makeup. He would even make comments about my weight when everyone else says I look beautiful . He stayed putting me down. I told him he needed to leave since he didn’t respect me and only had negative comments to say to me. I’m tired of feeling like a prisoner . He has been gone for two days and of course I feel sad but I cry random times seeing my kids look for their daddy. My dad has taken me and my children in and is telling me to put him on child support if he doesn’t reach out within two weeks. I’m not really sure how to feel I just know he was toxic but My kids miss him. How can I coparent if this man will not have a conversation like an adult. He left making it seem like he cares for them but then made a comment to me saying that he’ll have a big hole in his heart knowing he won’t see them again. I never told him he couldn’t see them and it makes me feel like he is plotting this to make it seem like he is the victim . I’m not really sure what to do I would never keep them away from him but I certainly need him to respect me as the mother of his child. This is just all too much. I’m still figuring out life now I have to be responsible completely on my own for my kids. I feel like I’m drowning . I don’t cry in front of them but my smile is surely fading . I need advice or words of wisdom . Im lost .