this statement can be very tricky but to but it in my way of thinking, she’s has made herself so unbreakable, she has formed herself into this “stone” which refers to her strength. But her strength is so strong that it is now questioned. the situation was that Shawn came home in a strange mood and asked Tara to get him water (impolitely) and Tara did but then she decided to spill it on his head. He then abused her, grabbed her by the hair, dumped her head in the toilet, and forced her to apologize until she couldn’t take the pain anymore.