What to do about my fiance..?

Becca

My fiance and I have been together 3 years in October. We are 8 years apart in age, him being 28 me being almost 21. We got pregnant with our first daughter 5 months into our relationship and moved to Maine July of 2016. Ever since being here he became different I think due to most his family and all his old friends being here. Anyways, when our first daughter was born he never helped me with her, especially during the nights. I didnt mind it so much then because I'm a stay at home mom and I could sleep when she slept during the day and he had to work. Since then we've taken in his little cousin who lost his dad in December 2016 and his mom sadly chose drugs over him. My MIL was taking care of him but now her health has gotten bad so she can no longer do it. Shortly after we moved all his stuff in, we found out I was pregnant again! I cried tears of fear when I saw that test turn positive... I always told him that when this baby was born, he'd be helping me more through the night since I was no longer able to sleep while our newborn slept because I now have 2 toddlers I'd be taking care of during the day. He said he would. Now she was born on April 20th and he hasnt helped unless he has absolutely had to or unless I ask him to and even when I do ask, he seems annoyed that I'm taking time away from his video games... Well tomorrow we have a guardian coming to check out the house so my fiance can get full guardianship of his cousin. I've been busting my ass cleaning and taking care of our 3 kids during the day and taking care of our almost 2 week old daughter completely by myself... Tonight I asked him to feed her so I could continue to clean since he was only playing his video games. He gets annoyed, starts complaining hes hot yet I'm the one running round the house getting shit ready for tomorrow. After he gets done feeding her he asks me to take her and so I ask him to move our bed for me since I'm really not even supposed to be lifting anything. Again, he gets mad at huffs and puffs saying hes tired... Yet he fell asleep at 7 last night and didnt get up for work till 7:15 this morning. Me on the other hand, didnt go to sleep till almost midnight and then was up at 2 4 and 6 with our newborn. So I get pissed and ask if hes the one losing sleep at night and then he somehow manages to flip it all back on me again... I'm honestly at a loss on what to do to get him to help take care of our kids and get his ps4 not to be his number one priority. Hell, we hardly even have a relationship anymore because he'd rather play games than spend time with me. I think about leaving every day but I feel like I just dont have what it takes to make it on my own with 2 kids under the age of 2 especially when I dont have my license, a vehicle of my own or a job...