well if you want to be separated and you think it would be healthier for you then you should do so .
no one can stop you but yourself from doing it .
Don't let him get in the way of you doing whats best for you .
any family you can stay with or friends ?
as for the divorce and him not wanting to get one - if i were you i would just focus on you getting a place to stay to be separated and the baby to come (:
those seem like the priorities .
once you are separated communication might be easier and less tension .
after the baby is born then focus on the divorce .
im sure after being separated for a certain amount of time he will get the msg .
good luck !