It seems like all of these Cat haters have only watched the show. In the books (Lady S aside) she overcomes her initial rage about Ned and what has been done to her family and she realizes having all of her children together and safe is much more important. Robb charges ahead rather blindly with vengeance but she wants more than that. Obviously her relationship with Jon is really upsetting but if what everyone thiks about Jons parents is true then Ned could have handled it differently.
Exactly. She begs Robb repeatedly to lay down his swords, and what does he respond with? He basically tells her at one point that she has forgotten her dead husband, because ROBB wants vengeance. Cat wants her children safe, as you said!! And tbh I like Ned a lot a lot but the way he handled the Jon situation was just fuckery even/especially considering R+L=J unless there's something about that whole deal that we don't know yet.
And if Cat is so obsessed with vengeance pre-Stoneheart... why didn't she just stab Jaime to death? He literally pushed Bran out a window and ADMITTED IT. It would have been easy to claim vengeance then and there, but she doesn't. Because getting her other children back is more important.
And I hate when people miss this because it takes away so much from the entire Lady Stoneheart arc--the entire tragedy in that is that Cat refrains, refrains, refrains from blood and vengeance... and then when she is revived she becomes ruthless.