Feel sorry for you. If I were you, I can't忍, I will shout to them and said: "你都唔係同仔女住,做冬正日都係同我地度食, you better mind your own business first."
I don't scare to have conflict with these三姑六婆. But I won't have a conflict to c6's mum.
Then I understand. I won't blame them but 99.
May be you need to learn how to 寸 them (incl. 99) with techniques, to let her that her way cannot make you surrender.