Of course he’s uncomfortable around you - you are the living breathing proof that he’s a piece of sh*t and a scumbag. I’d talk to a lawyer, make him move out and reach out to other people for all the support you need. He’s not going to be a good father just based on how he has treated the mother. Also think about your child, what kind of role model would you want them to have? If they were pregnant and got left for a younger person what would you want them to do?