Stop letting this vile man have any control over you and your life!
Keep the PG news a secret until after this shite has slinked back to whatever unfortunate nation that is unlucky enough to have him call it home. Mind you, if it's Egypt, GOOD, that place is welcome to him, he'll fit right in [dgrin] Deny this piece of work the opportunity to ruin your happy time. He can't make you unhappy if you don't have anything to do with him.
Go and visit your lovely PIL in the new year and tell them then, make it special without this dreadful person. Make alternative plans this year with your DH. This will be the last christmas you and he get to spend as a couple, as next year you will be a family!! 
If your BIL is not respecting his brother, by not respecting his brother's wife, then he will not respect your DC either. the Baby can be the catalyst you need to call FULL TIME on his contact with you and your child.
No-one will question your motives for staying away. TBH, your DH needed to say something and to say that there is no way on earth his B is allowed to be so rude to his DW.
You are in the right here you don't deserve this, you don't need to be the bigger person, but you need to draw a line and say, Er, no, I won't have it. He's no relative of yours, you owe him literally nothing.
Huge congratulations btw!!!