My boyfriends family ?!?

I'm in the same boat really, me and me fiance have been together for 3 years we've been through so much together since January last year me and his mum and sister haven't spoke and I will not talk to them, I speek to his dad and his gran but that's it, his sister starts on facebook all the time. I put on my facebook over xmas that my little girl loved all her christmas presents...... And his sister put back saying well at least her daddy buys her xmas presents as she aint having **** all of us she isn't wanted in our family, and that's there own flesh and blood. I've been called an unfit mother and everything from them and they don't have nothing to do with me or there granddaughter or niece, I'm gonna upset them tomorrow tho as I'm 12 weeks pregnant again so they defiantly won't like me then lol, I find it easier to block and delete them on facebook and just live your lifes together and be happy x