I am sorry that you are going through this. I can not imagine how hard it must be.
But what are you going to do moving forward?
It's very easy for me to say leave him forget him, and move on; but I know you understand him and would forgive him if you could. Yet, for whatever reason his mind is made on leaving and at the end of the day this is a blessing in disguise. Trust it.
You have something WAY bigger than this to worry about and it's your health and the baby growing inside you. Becoming desperate and depressed is directly affecting the health of the child. Go to therapy, church, listen to music, rest and eat everything your craving.
Let go, and bring that energy to your child. Move somewhere else if you can. Start new. This child can bring you more purpose and something greater to look forward to.
I really wish the best for you and will keep you in my prayers ! Take care.