4 months and depressed

I'll be 17 weeks tomorrow and my boyfriend just left me. We have a 3 year old and have been together for 6 years. This was supposed to be our new beginning because we have had many ups and downs, even a separation. While we was separated I was dating because it's the only thing I could do to not be miserable and hate life. I dealt with years of cheating from him after I had our daughter and when I confronted him about messages I found after he promised that he would no longer cheat he blew up and left me! I was lost and soo confused after that so I convinced myself that I should do as he was and doing behind my back and start giving my time to someone else. A few months later he came to me admitting all he has done and asking for another chance to be a family. I agreed because somehow after everything I still loved him and could only imagine a future with him. But since we agreed to full honesty I told him that I was seeing other men while we was separated. At first he said that we can move on and even apologized for doing things that led me to feel the need to start dating. When we found out I was pregnant in February we were so happy, and I was looking forward to actually having a happy and loving pregnancy but I was so wrong. It is now a year later since we started over and he says he can't get over the fact that I was with other men. He snaps at me for anything, absolutely anything! Curses me out if say the slightest thing to annoy him, even in front of the kids. He'll apologize and say he takes fault one day but then back to the same behavior a day after. Today he packed a bag and left telling me he hates me and while I'm distraught and crying he tells me I'm selfish because I'm going to make our unborn child have complications if I react this way. I'm left in the house with our 3 year old daughter and my 8 year old son and I somehow have to hide me emotions and take care of them. I dont know how I'm going to do this when I wish I was just dead right now. Don't even know what I'm going to feed them today because we live far from the store and he was supposed to drive me there before he decided to leave. I feel like I'm in the twilight zone, I have no one to talk to. No friends and I cant talk to my family because I don't want them to hate him. It was hard to get them in a good place with him after I told them about his cheating and leaving me 2 years ago. I wish I could disappear! This is crazy! So disgusted with my life right now.