Yes, boundaries are there for YOU.... definitely use them!
Originally Posted by
Bluehawaii 
So should it be ... I don't want to hear anymore stories about your dad.
This sounds like a great beginning - just finish the thought with what YOU will do if she crosses your boundary. It doesn't have to be an ultimatum or even anything that you explain to her - but the best boundaries contain both parts "If this-then that" so that when you are triggered, you don't need to stop & figure out what to do next because you already have your Plan B figured out.
"DD - I am asking you not to speak to me about your father anymore because it is not healthy FOR ME, I hope you can respect my boundary with this."
To Self - if she does bring him up, I'll leave the room/conversation/house/ask her to leave if we are at my home, etc.