A partner who does make your life easier is just another child

I'm posting this to get it off my chest because I don't really want to tell any of my friends or family. Mainly because I don't feel like hearing any lectures or "I told you so". Eventually I'll have to tell them but I guess I'm just not ready. I no longer want to be with my partner because I don't feel like he is my partner. I feel like I have a teenage boy living with me while I also have my actual toddler. I should have known but I just hoped that having a child would have made him grow up. Hes never willing to help with anything around the house unless I ask about 30 times and eventually get snappy at him and then of course I'm negative and nasty. He doesn't want to help with our son as well unless I beg him. I can't cook anything without being stressed out because my son is tall for his age and grabs everything he possibly can which makes the kitchen so much more unsafe and because of that i burn a lot of our food. He sits most of the time on his computer or he's sleeping and I'm fed up if it. We have argued about it so many times, we have had conversation and I have cried for days because he's just not willing to put in any work or effort into our family. His hobbies are more important than anything else and it drives me insane. I have been going through a lot of things recently in my personal life when it comes to mental health as I've been diagnosed with PTSD and awaiting my first therapy appointment and I've been finding it extremely difficult to stay positive. I always used to talk to my partner about these sort of things but recently he mentioned he's fed up of hearing how negative I am and it makes him not want to be around me. I understand that listening to negativity all the time can have an impact on you as well but it upset me when he said that so I've stopped saying anything to him about my mental health. If he asks if I'm ok I just say yeah I'm just tired and keep it moving. Just a few days ago I sat down with him to speak about everything I've just mentioned and his response was that he would just rather move out than change. He doesn't have to deal with me constantly nagging him about everything and he can just have his son on his days off work and when I said that I agree with him he started crying and said he still loves me. I swept it all under the rug hoping it was a wake up call for him but it wasn't. He's back to doing the same thing so I'm just going to end things with him for good. I'm just waiting on being able to be more independent and making sure I save up as much as I can before I do. I'm planning on doing it in a few weeks. I'm over being someone's maid, I'm over begging him to be a father and be present in his childs life. I don't care anymore. I have so much more that I need to focus on that I'm not able to. I'm still studying in university and I've sacrificed so much of my education to be a mother and he hasn't even been willing to sacrifices anything in his life. I'm done. I can do this by myself. All he does is give me more work than I need and isn't willing to help.