Children's fathers new girlfriend 😾

So I am currently 11 weeks pregnant and I also have a 2 year old son. They are both by the same man. My pregnancy this time was planned and he wanted to have this baby with me. When I found out I was pregnant I told him and he just snapped and said we're toxic for each other and I've been thinking this for a long time and he says we shouldn't be together. I wouldn't have let him get me pregnant if I knew he was going to do this to me... Now he has this new girlfriend and he claims she knows that he just recently got me pregnant and she's okay with it!!! That is so crazy who would be okay with that! I hate going through this pregnancy alone especially when I'm still in love with him. He still lives with me and he says that is what's best for our kids, but I'm really struggling. I really just need advice... I don't know what to do anymore. Any words of encouragement are welcome...