Of all the things wrong with this, what sticks out to me how he seemed to be offended when you put down your boundaries. I feel sorry for your sister and i would share this with her. If he behaves like this with his own family, it doesn’t bode well outside of it. Yeah, perhaps replying wasn’t the best idea but i cannot put myself in your position vis-a-vis your state of mind at the time but it doesn’t take away the lack of appropriateness of his comments.

It relates to stuk, which means broken in this context. It can also mean a piece. You could read it as (broken) into pieces.