Humiliated and devastated

so I've been seeing my kids father for like 8 years over the last two years it's been rocky!!!!! Anyhow we were still more or less an item in my eyes, I got pregnant with our second child due to have my baby is less than 4 weeks!!!!! So over the weeks I've started to discover this other woman. She's 18 young pretty, I can see why his head over heels. So his been promoting her on his social media posting pictures with her. So I asked her what's going on and we arranged to meet up, I met her we spoke she said she's 18 his 30 she doesn't intend on taking it anywhere but she's speaking to him, claims they haven't slept together. I've explained that he was only living in my house a few weeks ago we was a family and pooooooffff all of a sudden his gone. So we decided to go to see him at his work place me and his significant other, she didn't say much to him but I lost it with him I wanted to hear him say he didn't want me no more he more or less did anyway in so many words but not straight up. He humiliated me all his work mates were like tell her to shut up, ahhhh pissss offf you silly cow I was absolutely humiliated. 8months pregnant with his child and I felt so rejected. So since he hasn't even contacted me, neither has the girl. I think they are together and just trying to forget about the hurt they've caused me let alone my 4 yr old child plus the one on the way. I sat down and thought about it, I'm going to have to do this alone the labour as I have no support from family or friends and been quite honest I don't want him there either. The stress his caused is unbearable for me at the moment and not once ounce of compassion. Feel so stupid so angry I don't know what to do to move forward. His been slacking as a father aswell hasn't supported me muchthrough pregnancy, his stopped having our first born daughter too. I plan to just cut all strings, the more I see him the more hurtful it is so I've decided no contact. I ain't even gonna tell him when I've had the baby he doesn't deserve the opportunity to be there. People would say I'm wicked for not allowing him around but what the hell am I suppose to do. I can't force him to be a dad and the embarrassment he has caused me is unforgettable. #HELP!!!!!