I want out ASAP

My SO and I have been together on and off for over 7 years. We’ve had some really great times and some down right awful times. I thought I was sooo madly in love with him for years even though there were a lot of times where he’d treat me like shit. I haven’t been in love with him for at least 2 yrs and now we have a baby together. We weren’t technically together when we conceived our son. He desperately wanted to work things out and I just hadn’t had the D in months so I was down to have a fun time. I wasn’t on birth control and I tracked my ovulation. I had just been diagnosed with PCOS so I didn’t think I could have a baby but I always told him we couldn’t have sex during my ovulation because I didn’t want to get pregnant. But that time was different. I was ovulating and I told him and for some weird reason he decided to blow his lid in me which he neverrrrr did and so I was like ummm you need to buy me the plan b ASAP or there’s a possibility of us having a child. He said if I ended up pregnant he was ready and I said okay because like I said I was just diagnosed with pcos and I really didn’t think I could get pregnant. I thought maybeeeee there was a slight chance and if that were the case I was so ready no matter if I was with him or not.

Obviously I was pregnant and we decided to be together and work on things. He was such a dick during my pregnancy but of course there would be times where he wasn’t. I tried to have him leave soooo many times but he ended up refusing. His parents wouldn’t let him stay with either of them and I didn’t want him to sleep in his car otherwise I’d feel like the asshole. So we stuck it out. My son was born. All was well for a day or so. I had an emergency csection and other complications so when we got home I was ordered to be in bed and Jake was supposed to do all the diapers and what not. He was an asshole about it to the point where I ended up doing everything which caused me to have more complications with bleeding and what not.

Fast forward to 6 months later... we’ve had sex maybe 3-4 times. I have zero interest in being physical with him. I honestly forced myself into it tho king maybe it’s just my hormones. But I think I’m just sooo over it. I’m now a stay at home mom and he works which feels so weird because I was always the one making money not him. He gives me such a hard time if I ask him to watch the baby for a couple hrs or pay for diapers or wipes or little things. Yet he’s more than happy to pay for tattoos, shoes, clothes, and eating out. I’m done begging for him to contribute and to be kind about it. I just want to be out of the relationship and for him to pay child support so I don’t have to deal with him anymore. I don’t even care if he pays $100 a month for our child. I’m super thrifty and would find ways to make it work. Mind you I do make enough money to pay for my own bills just not my sons needs. I sell clothes online but it’s a lot harder now that I have a newborn. Just wanted to put that out there since I don’t want anyone thinking I’m just mooching off this guy. Everything we own in our home is because I bought it when I was making more when I had a second job and he never wanted to contribute.

So please, how do I go about this? Help.