He's probably scared - maybe he never really thought you'd get pregnant? Also, is there any chance his ex has said anything to him like "if you have another child I won't let you see DD?". Neither of these would be valid excuses for his behaviour, I'm just trying to think of a reason for him being such a d¡¢k. Whatever happens, I'm sure your bub will be lucky to have a mum who loves him/her.
"...dreaming of a belly full of life"