I guess my question is should i refuse her request to have any friendahip after divorce is final or leave that as a slight possibility in the future depending on her behaviour
If she brings up being friends after divorce I'd respond with something short. Like: "That's not a possibility for me."
Then walk away.
Remember, the more you engage with her the more damage you do. Be scarce. Be mysterious. As Cadet alluded to, the more you stay distant, the more she will wonder why.
