You say you won't accept shit, but it seems to me like you already are.
Until you stop making excuses for him he will continue to treat you like crap. I know you think you won't accept shit but I am seeing a young woman who thinks she isn't accepting shit when she already is.
I feel awful for you. I think you have a long rocky road ahead of you. He sounds horrible and you sound lovely.
You have been together such a short while, he is probably still on his best behaviour which is worrying. As time goes by you could possible see much more worrying behaviour.
I hope I am wrong, I hope that he is immature and when the baby is born he will get his act together. I hope he just needs some guidance, but I don't feel very positive about that.
And can I just say that I know people deal with grief differently but my teens lost their father a year ago and two grandparents to cancer. They are just kids but even they didn't treat people like crap over it. Sure, we had outbursts, but once with apologise after and they quickly tried to control it, and they are much younger and immature. His grief is a bullshit excuse to treating his mum the way he does.
I wish you all the luck in the word. You really do seem lovely and I hope that things change or you get the strength to leave him and eventually meet someone who deserves you.